from a total of 4 boys and 4 girls , how many 4 - person committees can be selected if the committee must have exactly 2 boys and 2 girls ?
"answer = b = 36 no of 4 person committees that can be formed = 4 c 2 * 4 c 2 = 36 answer b"
multiply(multiply(const_3, 4), multiply(4, 2))