(a) 14.90 rounded is 15, and 1.25 rounded is 1, so 15-1 is $14.
(b) My estimation will be high because I had to round up on the larger number and round down on the smaller number leaving a larger gap between the answer and the estimation.
(c) 14.90-1.25=13.65, so Pedro has $13.65 left in his wallet. But the difference between the estimation and the answer is 14-13.65=0.35 so its a $0.35 difference between the estimation and the answer for how much would be left in Pedro's wallet.
For this case, the first thing we must do is define variables.
x: amount of time Miguel uses to complete the task.
y: amount of time Maria uses to complete the task.
We write the system of equations:
x + y = 60
y = (1/2) x
Solving the system we have:
x = 40 minutes
y = 20 minutes
Answer:
it take her to wash them by herself about:
y = 20 minutes
He "owled" from the pain xD
