Question

When 6 new boys are admitted and 6 girls left from the class the percentage of girls decreased from 68 to 56 . Find orginal number of girls and boiys?

Answer 1

Answer:

boys=16

girls=34

Step-by-step explanation:

x boys

y girls

girls%=100*y/x+y=68

100y=68x+68y

68x-32y=0

17x-8y=0

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When 6 new boys are admitted and 6 girls left from the class the percentage

=100*(y-6)/x+y+6-6=56

100y-600=56x+56y

56x-44y=-600

14x-11y=-150

======================

187x-88y=0

112x-88y=-1200

subtract

75x=1200

x=1200/75=16

17*16=8y

y=17*2=34

boys=16

girls=34