Question

In a class there are 8 boys and 5 girls. Two class representative are to be chosen. In how many ways they can be selected if the first is to be a boy and the second any of the boy or girl? Solve step by step.​

Answer 1

Answer: 20

Step-by-step explanation: firstly we have pick a boy from 8 boys

then we have to pick any of the boy or a girl from 7boys (1 already picked) and 5 girls.(12 person in total)

=8P1 + 12P1

where P is permutation

8P1=8

12P1=12

=8+12

=20

Answer 2

Answer:

96

Step-by-step explanation:

the first person chosen MUST be a boy. So you have to choose 1 boy out of 8 boys. This equals to 8C1 (8).

The 2nd person can be EITHER a boy OR a girl. So now you have to choose 1 person out of the remaining total of 12. This equals to 12C1 (12).

Now, the question used the condition of AND, so you multiply your 2 answers together, like:

8C1 × 12C1 = 8×12

So answer is 96.