Percent Error Chemistry Measurement

A student estimated a mass to be 250g, but upon measuring it, found the actual mass to be 240g. What is the percent error?

A student measured the temperature of boiling water and got an experimental reading of 97.5 C. What is the percent error? (Tip: water boils at 100 C)

(nearest tenths)

An experimental measurement was taken of 10.4 mL and the actual measurement was 9.7 mL. What is the percent error?

The experimental calculation of the specific heat of aluminum was found to be 0.156 cal/gC, but the actual value was given as 0.185 cal/gC. What is the percent error?

A student measures a sample on a lab scale to be 62.5 g, but after realizing the scale was not properly balanced the actual mass of the sample was 57.8 g. What is the percent error?

(hundreths)