Question

Let * be a binary operation, on the set of all non-zero real numbers, given by a * b = ab/5 for all a, b ∈ R – {0}. Write the value of x given by 2 * (x * 5) = 10.

Answer 1

The given binary operation is a*b = ab/5

We have to find the value of x so that 2*(x*5) = 10

Firstly, x*5 = 5x/5 = x 

Now 2*(x*5) = 2*x = 2x/5 

As per the question, it is equal to 10 

∴ 2x/5 = 10 

∴ x = 25