5. Jill estimated a room to be 18ft tall. It was actually only 15 ft tall. What is her percentage of error? (tenth)
To calculate the percentage of error, we need to find the difference between Jill's estimate and the actual value, divide it by the actual value, and then multiply by 100 to convert it into a percentage.
Jill's estimate = 18 ft
Actual value = 15 ft
Difference = Actual value - Jill's estimate = 15 ft - 18 ft = -3 ft
Percentage of error = (Difference / Actual value) * 100
= (-3 ft / 15 ft) * 100
= -0.2 * 100
= -20
The percentage of error is -20%.