Rink entrance

There were 60 people at the rink, four-fifths of which were children under 15 years of age. A ticket for children under 15 costs €1 and for adults €2.
a) How many children were there at the rink?
b) How many adults were there?
c) How many euros did they collect for the entrance fee?

Final Answer:

a =  48
b =  12
c =  72 Eur

Step-by-step explanation:

$a=60\cdot 4/5=48$

$b=60-a=60-48=12$

$c=1\cdot a+2\cdot b=1\cdot 48+2\cdot 12=72\text{Eur}$

Try another example