Question

Ann puts a beaker on the scale which shows the mass to be 1.65kg. The actual mass was 1.72 kg. what was the percent error in Ann's reading ?
a)4.2 %
b)-7 %
c)- 4.1%
d)0.7%

Answer 1

Measured reading is 1.65 kg

actual reading was 1.72 kg

error in the reading is 1.72 - 1.65 = 0.07 kg

Now percentage error is given as

$error = \frac{error}{true reading}*100$

$error = \frac{0.07}{1.72}*100$

$error = 4.1$

so this is -4.1% error as the measured reading is less than the actual value