at a party there is an equal number of boys and girls. One quarter of the boys have part-time jobs. Twice as many of the girls have part - time jobs. Altogether 30 of those present are without part-time jobs.
Let x be the number of boys in the party?
Ok, let's go with that
So the number of boys is x , and so is the number of girls
Total at the party = 2x
boys with part-time jobs = x/4
girls with part time jobs = 2(x/4) = x/2
total part-timers = x/4 + x/2 = 3x/4
no part-time jobbers = 2x - 3x/4 = 5x/4
5x/4 = 30
x = 24
State any conclusion needed.