30g serving of a certain breakfast cereal has 0.5 g of salt. How much salt would that be in milligrams

In this problem, we are focusing only on the grams of salt, so the 30g is not useful information and can be ignored. To convert grams to milligrams, we want to move the decimal to the left 3 spaces. We know it should move to the left, because we are moving to a smaller unit of measurement.

.5

.0005 milligrams of salt