I used excel to calculate
the answers are 798, 1726 and 2654
Basically your child should do what excel does:
1) Write column A of numbers 1,2,3,4 ... 100
2) Write column B with calculation result of "column A number * 32 + 30" =
3) Write column C with calculation result of "column A number * 58 + 44" =
4) Then go over the results and find numbers that are the same in column B and C