the ratio of the number of kids is 4:7
that means for every 7 kids we have 4 adults
7 kids ---- 4 adults
the difference is 3
we dived the difference of the kids between the difference of the ratio
150/3 = 50
the number we obtained must be multiply by the ratio of each part
7(50) = 350 number of kids
4(50)=200 number of adults
there are 200 adults at the fun fair