Open Up - Grade 7 - Mathematics - Unit 4 - Lesson 14

A student estimated that it would take 3 hours to write a book report, but it actually took her 5 hours.

What is the percent error for her estimate?

A radar gun measured the speed of a baseball at 103 miles per hour.

If the baseball was actually going 102.8 miles per hour, what was the percent error in this measurement?(Round so there are only a maxium of 2 values to the right of the decimal for the percentage.)

It took 48 minutes to drive downtown. An app estimated it would be less than that.

If the error was 20%, what was the app’s estimate?(Round to the nearest tenth.)

A farmer estimated that there were 25 gallons of water left in a tank.

If this is an underestimate by 16%, how much water was actually in the tank?(Round to the nearest tenth.)

For each story, write an equation that describes the relationship between the two quantities.

Diego collected x kg of recycling. Lin collected

more than that.

For each story, write an equation that describes the relationship between the two quantities.

Lin biked x km. Diego biked

less than that.

For each story, write an equation that describes the relationship between the two quantities.

Diego read for x minutes. Lin read

of that.

For each diagram, decide if y is an increase or a decrease of x. Then determine the percentage.

Lin is making a window covering for a window that has the shape of a half circle on top of a square of side length 3 feet.

How much fabric does she need?(Round to the nearest tenth.)