Tune in to Learning


Salt: Math Lesson: Activity 1 of 3

Prev ActivityNext Activity


Table salt is a compound of the two chemical elements sodium and chlorine. If you want to keep track of the amount of sodium you eat every day, you’ll need a way to measure it. Sodium in food is measured in milligrams (mg), a metric unit that measures mass.

“Milli” means “one thousandth,” or 1/1,000, so milligram means 1/1,000 of a gram. A gram (g) is about the weight of a small paper clip. If you broke that paperclip into 1,000 pieces, each piece would weigh 1 mg. In math terms this means:

1 mg = 1/1,000 gram (1 mg is 1/1,000 of a gram.)
Which is the same thing as:
1,000 mg = 1 g (There are 1,000 mg in 1 gram.)

To convert grams to milligrams: multiply the number of grams by 1000.

To convert milligrams to grams: divide the number of milligrams by 1000.

Drag and drop each measurement in the order from least to greatest. Hint: Use a piece of paper and convert all measurements to one unit—either grams or milligrams—before putting them in order from least to greatest.

1.5 mg
24 mg
0.5 g
2,800 mg
1,000 g
Question 2 of 3