In a club, the ratio of the number of adults to the number of
children is 12 :7. The ratio of the number of boys to the number of
girls is 3 : 2. If there are 42 girls, how many members are there
altogether?

solution :------

Let the Number of adults = 12x

and the number of children = 7x

According to question ,

Number of boys / number of girls = 3/2

Number of boys = 3/2 * number of girls.

Given , Number of girls = 42

Therefore Number of boys = 3/2 * 42

= 3*21

= 63

**Therefore Number of Boys = 63**

Both Boys and girls are children , therefore number of Children = number of boys + number of gilrs

= 63 + 42

= 105

**Number of children = 105 **

therefore , 7x = 105

=> x = 105/7

=> x = 15

Hence Number of Adults = 12 x

= 12 * 15

=** 180**

Therefore , total members = adults + children

= 180 + 105

= **285**

Hope this helps you !!!

Thank You !!