Question

trei elevi aveau 1560 lei.dupa ce a cheltuit primul 75% , a doilea 80%, iar al treilea 2/3 din suma sa, lea ramas sume egale. ce suma a avut la inceput fiecare

Answer 1

a+b+c=1560
a-75%a=b-80%b=c-2c/3
25%a=20%b=c/3
a/4=b/5=c/3
b=5a/4
c=3a/4
a+5a/4+3a/4=1560
4a+5a+3a=6240
12a=6240
a=520 lei
b=520×5/4=650 lei
c=520×3/4=390 lei