Me asap 9-13 and do the exact answer to pls

For these you would first round the numbers to an even ten or maybe 5 then multiply them by eachother. Then use a calculator to find the exact answer. For example 9 would be 40 x 90~ 3600 then the exact answer would be 3496

9: Estimated: 30*90= 2700| Real 3496
10: Estimated: 8*4= 32| Real answer= 34.02
11: Estimated: 8*1=8| Real answer= 6.885
12: Estimated: 4*6=24|Real answer= 22.876
13: Estimated: 1*1=1| Real answer=0.918