Question

Out of 2000 families with 4 children each, how many would you expect to have (a) at least 1 boy (b) 2 boys (c) 1 or 2 girls (d) no girl.

Answer 1

Answer:

Step-by-step explanation:

4 children each

There can be 16 ways to have boys & girls if 4 children in a family

B    B    B   B

B    B    B   G

B    B    G    B

B    B    G    G

B    G    B    B

B     G   B    G

B    G    G    B

B    G    G   G

G    B    B   B

G    B    B   G

G    B    G    B

G    B    G    G

G    G    B    B

G     G   B    G

G    G    G    B

G    G    G   G

at least 1 boy = 1  - No boys

= 1  - 1/16

= 15/16

2000 * 15/16  = 1875 families   at least 1 boy

2 boys = 6/16  =  3/8

Families = 2000 * 3/8  = 750  families with exact two boys

1 or 2 Girls  =  10/16  =  5/8

Families = 2000 * 5/8  = 1250  families with 1 or 2 Girls

no Girl  = 1/16  

Families = 2000/16  = 125 families with no Girl