Question

Alicia and Jeremy weigh a cell phone on a digital scale. They write down 113 but forget to record the unit. Which unit of measurement is correct? How do you know?

Answer 1

For this case, what you should keep in mind is that the unit that must be written next to the number is a unit of mass.

The unit of mass in the international system is kilograms or equivalently:

m: [Kg]

We know that physically it is impossible for a phone to weigh 113 kilograms.

Therefore, a unit of equivalent mass must be written.

An ideal weight, would be for example:

113 grams

Note: the conversion between kilograms and grams is:

1 kilogram = 1000 grams

Answer:

A unit of measurement that is correct can be:

113 grams

Answer 2

I'm sure the measurement was made in grams because:

1. most cell phones weigh between about 100 and 150 grams
2. there's no cell phone that weighs 113 kg, 113 pounds, 113 ounces etc.