Exams › SSC CGL (Prelims) › General

If a^3 + b^3 = 280 and a + b = 10, find the value of ab.

1. 24
2. 26
3. 28
4. 22

Correct answer: 24

Solution

Using a^3 + b^3 = (a + b)^3 - 3ab(a + b): 280 = 1000 - 3ab(10), so 30ab = 720 and ab = 24.

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