Aptitude - Numbers - Discussion
Discussion Forum : Numbers - General Questions (Q.No. 111)
111.
If (64)2 - (36)2 = 20 x x, then x = ?
Answer: Option
Explanation:
20 x x = (64 + 36)(64 - 36) = 100 x 28
 x = |
100 x 28 | = 140 |
| 20 |
Discussion:
4 comments Page 1 of 1.
Pooja Yadav said:
4 years ago
(64)^2 - (36)^2 = 20 * x.
There is a formula;
a^2 " b^2 = (a +b)(a - b),
(64)^2 - (36)^2= (64+36)(64-36),
Put it in question.
(64+36)(64-36) = 20*x.
100 * 28 = 20x.
X = 100*28/20.
X = 140.
There is a formula;
a^2 " b^2 = (a +b)(a - b),
(64)^2 - (36)^2= (64+36)(64-36),
Put it in question.
(64+36)(64-36) = 20*x.
100 * 28 = 20x.
X = 100*28/20.
X = 140.
Bhagya kunduru said:
4 years ago
I can't understand. Please explain for me.
Vijay said:
5 years ago
Here the formula is (a^3-b^3)=(a-b)*(a+b).
Deepak bhattarai said:
8 years ago
How it becomes (2nd step from 1st step)
x=100*28/20?
Please explain.
x=100*28/20?
Please explain.
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