The number would be 21 because if you add 5+37 then divide by 2.Younwill get the answer

to solve for j first you need to cross multiply;
j × 35 = 42 × 55
35j = 2,310
j = 2,310 ÷ 35 (did the inverse operation)
j = 66
Hope that helps :D
The answer is 50625 because 5*3 is 15 and take that to the power of 4