Answer:
$40 / x ; $10 / y
Step-by-step explanation:
1.)
For the question, the number of girls aren't given ;
Assume the number of girls = x
The total amount they agreed to spend between themselves = $40
Amount spent on average :
Total amout to be spent / number of girls
Amount spent on average by each girl = $40 / x
2.)
The cost of ice cream isnt given;
Assume, cost per ice cream $y
Amount to be spent on on ice-cream = $10
Number of ice creams that can be purchased :
Amount to be spent on ice-cream / cost per ice cream
$10 / y