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Maths Puzzle
Let N = 553+ 173- 723. N is divisible by
A.Both 7 and 13
B.Both 3 and 13
C.Both 17 and 7
D.Both 3 and 17
Read Solution (Total 3)
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- N = 553+ 173- 723 = 3
which is divisible by 3 only. - 11 years agoHelpfull: Yes(4) No(2)
- I think Question is 55^3+17^3-72^3
Ans: 3 and 17
Soln:
55^3+17^3-72^3 CAN BE WRRITEN AS ((55+17)(55^2-55*17+17^2))-72^3 //use a^3+b^3 formula
((72)(55^2-55*17+17^2))-72^3)
72(55^2-55*17+17^2-72^2) //Taking 72 as common
72((55+72)(55-72)-55*17 +17^2)
72((128)(-17)-55*17 +17^2)
72*17( 128- 55*17 +17^1) //Taking 17 as common
Now 17 and 72 Will be divisible by 17 and 3
Thus solved
- 11 years agoHelpfull: Yes(4) No(0)
- I think Question is 55^3+17^3-72^3
Ans: 3 and 17
Soln:
55^3+17^3-72^3 CAN BE WRRITEN AS ((55+17)(55^2-55*17+17^2))-72^3 //use a^3+b^3 formula
((72)(55^2-55*17+17^2))-72^3)
72((55^2-55*17+17^2)-72^2) //
- 11 years agoHelpfull: Yes(0) No(0)
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