To make it easy we can multiply 5 and 0.8 times 10 before we start dividing. The result will no change because we multiplying both numbers by the same number.
5*10=50
0.8*10=8
No we can divide 50:8
6,25 - its the result
50:8
48
20
16
40
40
0
Hope that helps.
31. +
34. -
To figure out more, just solve the known problem, and then go over what the answer would be to the unknown one until you find the answer that makes it true.
rate of blowing balloons of Alexa = 15/20 = 0.75
rate of blowing balloons of Sara = 18/25 = 0.72
rate of blowing balloons of Shirley= 16/21 = 0.76
rate of blowing balloons of Sam = 12/23 = 0.52
from above calculation we concluded Shirley can blow balloons at the fastest rate!
