Question

The capacity of an elevator is either 25 children or 19 adults. If 10 children are currently in the​ elevator, how many adults can still get​ in?

Answer 1

For every 19 adults, there are 25 children;
For every 1 adult, there are $\frac{25}{19} children$
1 adult is equivalent to 1.3157 children
After 10 children get on board, there is space for 15 children;
1 adult= 1.3157 children
?          =15children
=$\frac{15*1}{1.3157}$
= 11 adults