Select all that apply.

which of the following expressions could you use to estimate 47% of 89?

1/2 · 90
0.5 · 90
0.47 · 89
90/2

Given: 
47% of 89

Exact solution is : 0.47 * 89 = 41.83

Estimates: you round the number to the nearest tens.
47% can be 50% ; 89 can be 90

0.50 * 90 = 45

50% is the same as 1/2
1/2 * 90 = 45

90/2 is also applicable to estimate for the above figure. 90/2 = 45

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post