Mental Math

4 + 7 + 2 + 8 + 3 + 6 + 9

25 + 47 + 75

24 + 26 - 50

45 and what adds to 100?

4 x 8 = 32 and 2 x 16 equals 32...

if 9 x 8 = 72, what times 4 equals 72?

2 x 8 x 5

All together, 5 groups of 7

45 split into groups of 5, how many groups?

25 x 2 x 7

50 x 2 x 16