Compatible numbers are those numbers which are close in value to the actual numbers, and they make it easy to perform mental arithmetic.
So here the dividend is 2596 and divisor is 6. So compatible number should be such that can be mentally divided by 6.
So the compatible numbers are = 2400 and 3000
So when we divide 2400 by 6 we have =
2400/6 = 400
And when we divide 3000 by 6, we have =
3000/6 = 500