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A PINCODE is of 5digits. The first digit is square of the second. Sum of the second and third is 10. The fourth is equal to the second plus 1. The third plus fifth makes 14. Sum of all digits is 30. WHAT IS THE PIN CODE

93747

93747 shikenah

ThatFairGuy:
A PINCODE is of 5digits.
The first digit is square of the second.
Sum of the second and third is 10.
The fourth is equal to the second plus 1.
The third plus fifth makes 14.
Sum of all digits is 30.
WHAT IS THE PIN CODE

Let the digits be=abcde
a=b<sup>[/sup]2
b+c=10
d=b+1
c+e=14
a+b+c+d+e=30

c=10-b
e=14-c

b[sup]</sup>2+b+(10-b)+(b+1)+(14-c)
But c=10-b
b^{[/sup]2+b+(10-b)+(b+1)+(14-(10-b))
Open the bracket and collect like terms
b[sup]}2+2b-15=0
(b<sup>[/sup]2+5b)-(3b-15)=0
b(b+5)-3(b+5)=0
(b-3)(b+5)=0
b=3 or b=-5

a=b[sup]</sup>2=3[sup][/sup]2=9
b=3
c=10-3=7
d=b+1=3+1=4
e=14-c=7

9+3+7+4+7=30

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