SELF Exam Logical Reasoning Mathematical Reasoning

IF 3 = 21
4 = 56
5 = 115
hence find value of 8

Read Solution (Total 5)

IF 3 = 21
4 = 56
5 = 115

3*(3^2-2) => 3*7 = 21
4*(4^2-2) => 4*14 = 56
5*(5^2-2) => 5*23 = 115
Similarly
8*(8^2-2) => 8*62 = 496

Ans : 496
10 years agoHelpfull: Yes(12) No(0)

3^3-(3*2)=21
4^3-(4*2)=56
5^3-(5*2)=115
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.
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8^3-(8*2)=496
10 years agoHelpfull: Yes(1) No(0)
3*7=21,7+7
4*14=56,14+9
5*23=115,23+9
8*32=256
so ans is 256
10 years agoHelpfull: Yes(0) No(0)
x=x^3-x*2
similarly
8=8^3-8*2=496
10 years agoHelpfull: Yes(0) No(0)
if 3=21 :3*7
4=56 :4*14
5=115 :5*23
similarly
6=204 :6*34
7=329 :7*47
8=496 :8*62
9 years agoHelpfull: Yes(0) No(0)

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