7/7 = x
3/7 = 240
7/7 x 240 = 240
240/ 3/7 = 560
there is 560 kids
560-240(all kids - girls)
there is 320 boys
Yeah you have to regroup and if this app doesn't help you can go to a library that has homework help p.s. this is a tip
This is just substitution. so 3(2(3)-4(1/2)+3(-2/3)= 3(6-2-2)= 3(2) = 6. Basically you plug in the values they gave you for the variables and then just solve one step at a time