₦airaland Forum

Welcome, Guest: RegisterLoginWith GoogleTrendingRecentNew

Stats: 3,326,078 members, 8,424,897 topics. Date: Thursday, 11 June 2026 at 06:55 PM

Toggle theme

Mathematician Over To You? - Education (4) - Nairaland

Nairaland ForumNairaland GeneralEducationMathematician Over To You? (27749 Views)

1 2 3 4 5 6 7 8 9 Reply (Go Down)

Re: Mathematician Over To You? by efemena5050(m): 1:08pm On Aug 17, 2025
Stainlezzking:
the two people above me, saying $10 is funny. he made $20 in total.
.
Re: Mathematician Over To You? by PrinceAsanike: 1:08pm On Aug 17, 2025
This is very simple, and I do not know why you are calling mathematician, any person can solve it. However, I am surprised at some people missing the answer. The answer, unarguebly is N20.

The first time he made N10 profit, likewise the second time, making it a total of N20 profit. So easy.

Let assume he borrowed money to buy in the first time, he would just collect hiis N10 profit and return N60 to the creditor. The same for second business
Re: Mathematician Over To You? by SpecialAdviser(m): 1:08pm On Aug 17, 2025
CJStarz:
Total loss.
He made nothing
You are a business illiterate
Re: Mathematician Over To You? by femi4: 1:08pm On Aug 17, 2025
Thunderfayamods:
What of the money he paid to buy it back! He made nothing!
Hope this helps

20 dolls

Buy for 60 → cash –60

Sell for 70 → cash –60 + 70 = +10

Buy back for 80 → cash +10 – 80 = –70

Sell for 90 → cash –70 + 90 = +20
Re: Mathematician Over To You? by joluwaseyi866: 1:09pm On Aug 17, 2025
Says it all

Re: Mathematician Over To You? by Sammy0787: 1:09pm On Aug 17, 2025
Another way of analysing it, is that he started a business with $60 dollars
He made profit of $10
and he later borrowed $10 (i e from $70-$80)
He made another profit of $10
And now his Capital is $80
His loan is $10
That means he has made profit of $20
Re: Mathematician Over To You? by xristos(m):
He made 20.
So u have 100k in ur hand. U want to invest so u go and buy an iPhone 7 for 100k so u can resell.

U resell it for 110k. Now u think u have 10k gain if u take out ur capital. But u want to buy the next phone to sell and it now costs 120k

U go and borrow 10k from ur friend to complete the money and buy the new phone. Then resell it for 130k

After selling for 130k, u have to return the 10k u borrowed from ur friend. Meaning u have 120k in ur hand
Re: Mathematician Over To You? by TheBizGenius: 1:09pm On Aug 17, 2025
Imagine.

I am so sure people who are saying $0 or $10 are not goods traders in real life. Lol.

This is why Ibo boys in container shops seem to do better financially in real life than the extremely educated folks in Nigeria.

For people who don't know, this is not a BUSINESS question. It's a TRADING question. Don't overthink it; it's just money in, money out.

Any trader who engages in selling things daily knows it's simply $20.
Re: Mathematician Over To You? by IEJames(m): 1:10pm On Aug 17, 2025
He traded twice
He made 10 dollars profit from the first

He also made 10 dollars from the second
TOTAL PURCHASE 60 & 80 -- 140
TOTAL SALES 70 & 90 -- 160

Net profit 160 - 140 ---- 20 dollars


Seperate transactions, seperate profits. No confusion!
Re: Mathematician Over To You? by friday2011(m): 1:10pm On Aug 17, 2025
20$ bro, opening balance is $60 plus additional $10 for the second purchase. closing balance is 90$

$90 minus $70

Profit....$20
Re: Mathematician Over To You? by Dzzzz: 1:11pm On Aug 17, 2025
That’s no business..
Re: Mathematician Over To You? by irepnaija4eva(m): 1:12pm On Aug 17, 2025
Nicoddemus:
What a stupid business man grin


Obviously not an Igbo man cause he made no profit.

Unfortunately some business are just like this very man and that's why many businesses crash. They don't know how to separate profit from capital. The continually spend all their profit without putting some back th the business to increase it's shock absorbing capacity or their expenses are more than their profit so there encroach on their capital money. Unknowingly for them the business purchasing power is and is crashing down gradually without their knowledge till a minor challenge crashes the business grin
The only right answer here...
Others above na big dolo. .
Re: Mathematician Over To You? by PuZZyNegro: 1:12pm On Aug 17, 2025
Juliearth:
1st deal

Buys goat = $60

Sells goat = $70

Profit = $70 – $60 = $10


2nd deal:

Buys goat again = $80

Sells goat = $90

Profit = $90 – $80 = $10


Total profit from both deals= $10 + $10 = $20
Following your calculations, he made $10 when he sold for $70.

Now, he went to buy back the same product but this time, he added the $10 profit to the $60 initial capital and borrowed $10 to purchase the item, leaving him with no initial gain anymore but $10 debt.

The he sold the product for $90. He will first remove the $10 borrowed, leaving him with $80. The total profit will now be $20. The reason is because, if he set out with $60 and is returning with $80, he's had additional $20 irrespective of how many transactions were performed to achieve that.
Re: Mathematician Over To You? by Princewell2012(m): 1:14pm On Aug 17, 2025
wwwihy:
This is Accounting, not Mathematics

$20.

Explanation:
First trade: Bought for $60, sold for $70 → profit $10.
Second trade: Bought back for $80, sold for $90 → profit $10.
Total profit = $10 + $10 = $20 (ignoring any other costs
You're wrong sir, yes he made 10 buks on his first purchased, but he added the ten bucks because of the inflation to buy it back at 80 then selling it for 90. So he is only making Ten dollars only instead of 20. So had it been he still buys it at 70 then he will be making $20 altogether.
It is actually a very logic question.
Re: Mathematician Over To You? by chasteman(m): 1:16pm On Aug 17, 2025
He made. $0
Re: Mathematician Over To You? by kingyang: 1:16pm On Aug 17, 2025
muyico:
Simple equation but logic! Who can solved this equation??
Alright, let's break down the problem step by step to understand how much profit the man made from these transactions involving the goat.

### Understanding the Problem

We have a sequence of buying and selling actions:

1. **First Purchase:** Buy a goat for \$60.
2. **First Sale:** Sell the goat for \$70.
3. **Second Purchase:** Buy the goat again for \$80.
4. **Second Sale:** Sell the goat again for \$90.

Our goal is to calculate the total profit made from these transactions.

### Calculating Profit Step by Step

**Profit** in such transactions is calculated by considering the money spent (costs) and the money earned (revenue). The total profit is the total revenue minus the total cost.

Let's list out the inflows (money received) and outflows (money spent):

1. **First Purchase:**
- Action: Buy goat
- Amount: \$60 (outflow)

2. **First Sale:**
- Action: Sell goat
- Amount: \$70 (inflow)

3. **Second Purchase:**
- Action: Buy goat again
- Amount: \$80 (outflow)

4. **Second Sale:**
- Action: Sell goat again
- Amount: \$90 (inflow)

Now, let's sum up the inflows and outflows separately.

**Total Outflows (Money Spent):**
- First purchase: \$60
- Second purchase: \$80
- **Total spent:** \$60 + \$80 = \$140

**Total Inflows (Money Earned):**
- First sale: \$70
- Second sale: \$90
- **Total earned:** \$70 + \$90 = \$160

**Total Profit:**
- Profit = Total earned - Total spent
- Profit = \$160 - \$140 = \$20

### Verifying with Individual Transactions

Sometimes, it's helpful to look at the profit from each buy-sell pair to ensure our answer makes sense.

1. **First Buy-Sell Cycle:**
- Bought for \$60, sold for \$70.
- Profit: \$70 - \$60 = \$10

2. **Second Buy-Sell Cycle:**
- Bought for \$80, sold for \$90.
- Profit: \$90 - \$80 = \$10

**Total Profit:**
- \$10 (first cycle) + \$10 (second cycle) = \$20

This matches our previous calculation, confirming that the total profit is indeed \$20.

### Potential Missteps

It's easy to get confused when the same item is bought and sold multiple times. One might mistakenly think to subtract the selling prices from the buying prices in sequence without considering that each sale is independent of the previous purchase after the first sale.

For example, someone might think:

- First sale: \$70 - \$60 = \$10 profit.
- Then buys again for \$80: thinks they're now at a loss because \$80 is more than \$70, but this isn't correct because the first transaction is already closed with a \$10 profit.
- Then sells for \$90: \$90 - \$80 = \$10 profit.
- Total: \$10 + \$10 = \$20.

This approach also leads to the correct answer, but it's crucial to recognize that each buy-sell pair is independent in terms of calculating profit.

### Alternative Approach: Net Cash Flow

Another way to look at it is to track the net cash flow at each step, starting from \$0.

1. **Start:** \$0
2. **Buy for \$60:** -\$60
3. **Sell for \$70:** -\$60 + \$70 = +\$10
4. **Buy for \$80:** +\$10 - \$80 = -\$70
5. **Sell for \$90:** -\$70 + \$90 = +\$20

At the end, the net is +\$20, which is the total profit.

### Conclusion

After carefully analyzing the transactions through multiple methods—summing total inflows and outflows, calculating profit per buy-sell cycle, and tracking net cash flow—we consistently arrive at the same conclusion.

**Final Answer:** The man made a total profit of **\$20**.
Re: Mathematician Over To You? by xristos(m):
joluwaseyi866:
Says it all
AI still needs some human intelligence
Re: Mathematician Over To You? by Lanre1st(m): 1:18pm On Aug 17, 2025
He make $80. His profit is $20
Re: Mathematician Over To You? by efemena5050(m): 1:18pm On Aug 17, 2025
The question is incomplete and ambiguous

Now assuming he never borrowed to finance his deficit
Total revenue after gross deduction = Adjusted net profit will be 10$

Let's assume he borrowed to finance his deficit (10 $) then grossprofit will be 20 dollars

But in all total grossprofit-cost of goods sold
Will be 10$


Since no follow up of how the 10$ deficit came up from where hence he was able to buy the goat at 80$


In all his net income from the business is 10$
If u must contend this then u should come prepared
Re: Mathematician Over To You? by unscripted(m): 1:19pm On Aug 17, 2025
Jashub:
Sorry to say but you definitely did not comprehend the question
he made 20$, he invested 60$ at the begining , later added 10$ , that makes it 70 $ his final return was 90$ , so he made 20$ at the end
Re: Mathematician Over To You? by 081dot: 1:19pm On Aug 17, 2025
He made nothing, not until he buys again at a cheaper price and was able to sell at higher rate and that will be his gain.
0$

If you are doing business like this, your advantages is that as the economy rises you rise with it. But with the illustration above, he went to sort out 10$ again and gained that 10$ back. After he returned it he will be back to the capital with no gains. Ire ooo
Re: Mathematician Over To You? by Ezzymadu(m): 1:19pm On Aug 17, 2025
Stainlezzking:
the two people above me, saying $10 is funny. he made $20 in total.
You don't understand the question we are talking of profit at hand at the end of trading he even invest extra 10k to buy it back so at the end he made 10k if not nothing at all
Re: Mathematician Over To You? by Nobody: 1:25pm On Aug 17, 2025
Nicoddemus:
What a stupid business man grin


Obviously not an Igbo man cause he made no profit.

Unfortunately some business are just like this very man and that's why many businesses crash. They don't know how to separate profit from capital. The continually spend all their profit without putting some back th the business to increase it's shock absorbing capacity or their expenses are more than their profit so there encroach on their capital money. Unknowingly for them the business purchasing power is and is crashing down gradually without their knowledge till a minor challenge crashes the business grin
You're not an igbo man, bro.

Le ya otiowa

Quick ledger:

Buy 1: cash −60, inventory +1

Sell 1: cash +70 → net +10, inventory 0

Buy 2: cash −80, inventory +1

Sell 2: cash +90 → net +10, inventory 0

Cash increased by $20 overall, so total profit is $20.

Another way Kwa,

Compare totals:
Total spent = 60 + 80 = 140

Total received = 70+90=160.

Net = 160−140=20.

Another way to reason it.

Start with $C cash, no goat.

End with no goat (sold it) and cash $C + 20.

The fact that the first $10 became part of the second purchase price doesn’t change profit.
it just changes how the purchase was funded.
Re: Mathematician Over To You? by jrobbins: 1:26pm On Aug 17, 2025
He made nothing.

No profit no loss
Re: Mathematician Over To You? by Princewell2012(m): 1:26pm On Aug 17, 2025
lezan:
$20 cause the initial investment were is money and whatever on it on both occasions becomes interests, forget the grammer of he buys it again. The moment he sold the first time, it was no longer his, the transaction ended that instance. The next time he went to to market , priced changed and he still made profit after selling second time. So total profits made is $20, no more no less
What are you saying sir, that I used my former gain add it up to buy back, so what is my gain? Remember this time the price have changed.
In fact if I removed my expenses, I will have nothing left with me.
But on the book I can just say I have made ten dollars since I have decided to sell it at $90 .
Re: Mathematician Over To You? by Mandesz(m): 1:27pm On Aug 17, 2025
muyico:
Simple equation but logic! Who can solved this equation??
He made nothing i.e Break-evem
Re: Mathematician Over To You? by IMPARTIAL: 1:28pm On Aug 17, 2025
You are all wrong!

He made 30 bucks.
Re: Mathematician Over To You? by dgitrader(m): 1:28pm On Aug 17, 2025
.
Re: Mathematician Over To You? by Nobody: 1:28pm On Aug 17, 2025
Just ask A. I.
It is highly likely that those who gave the correct answers to that did not even make use of their mind to really solve that .
A. I was used .
Welcome to the world of AI
Re: Mathematician Over To You? by Mandesz(m): 1:28pm On Aug 17, 2025
He made nothing. Yes
Phnuel007:
You're not an igbo man, bro.

Le ya otiowa

Quick ledger:

Buy 1: cash −60, inventory +1

Sell 1: cash +70 → net +10, inventory 0

Buy 2: cash −80, inventory +1

Sell 2: cash +90 → net +10, inventory 0

Cash increased by $20 overall, so total profit is $20.

Another way Kwa,

Compare totals:
Total spent = 60 + 80 = 140

Total received = 70+90=160.

Net = 160−140=20.

Another way to reason it.

Start with $C cash, no goat.

End with no goat (sold it) and cash $C + 20.

The fact that the first $10 became part of the second purchase price doesn’t change profit.
it just changes how the purchase was funded.
Re: Mathematician Over To You? by franugo(m): 1:29pm On Aug 17, 2025
Tboy222:
You are absolutely correct
He absolutely is not....let's look at it this way, take the total cost price and selling price for both transactions separately.

Total cost is 60+80 = 140
Total selling price is 70+90 = 160
Total profit is $20
Re: Mathematician Over To You? by Princewell2012(m): 1:29pm On Aug 17, 2025
adexbols:
He invested $70 and made $90

Profit is $20
But there was an inflation along the lines, so which is going to pay for the difference. Remember this is $10 dollars increase in his second purchase?
1 2 3 4 5 6 7 8 9 Reply

Mathematician In The House, Help MeEmmanuel Nworie, First-Class Mathematician & Farmer Bags PhD Scholarship*inside The World Of First-class Mathematician Languishing On Ebonyi Farmland(pi234

2016 Most Popular Careers Among Nigerian StudentsUNILAG TV: First University TV Station In Nigeria Begins Operation On January 17Nigerian School Goes Viral For Teaching Students A Foreign Accent (photos/video)