Converting Measurements — Answer Key
Part A: Fix the Sentence
Each sentence has an error. Rewrite it correctly on the line.
1. Fix the sentence:
1 kilometer = 100 meters
Corrected: 1 kilometer = 1,000 meters. There are 1,000 meters in every kilometer.
The original said 100 meters, but 1 kilometer actually equals 1,000 meters because the prefix 'kilo' means 1,000.
2. Fix the sentence:
4 kilograms = 400 grams
Corrected: 4 kilograms = 4,000 grams because there are 1,000 grams in 1 kilogram and 4 × 1,000 = 4,000.
Since 1 kilogram = 1,000 grams, you multiply 4 × 1,000 to get 4,000 grams, not the 400 grams stated in the original sentence.
3. Fix the sentence:
30 millimeters = 30 centimeters
Corrected: 30 millimeters = 3 centimeters because there are 10 millimeters in 1 centimeter and 30 ÷ 10 = 3.
There are 10 millimeters in 1 centimeter, so you divide 30 ÷ 10 = 3 centimeters. The original incorrectly said 30 centimeters without dividing.
Part B: Fill in the Blank
Write the missing word or number on each line.
1. 6 meters = 600 centimeters
Since 1 meter = 100 centimeters, multiply 6 × 100 to get 600 centimeters.
2. 9,000 grams = 9 kilograms
Divide 9,000 by 1,000 because there are 1,000 grams in each kilogram, giving 9 kilograms.
3. 2 kilometers = 2,000 meters
Multiply 2 × 1,000 because each kilometer contains 1,000 meters, so 2 kilometers = 2,000 meters.
4. 80 millimeters = 8 centimeters
Since 10 millimeters make 1 centimeter, divide 80 ÷ 10 to get 8 centimeters.
Part C: Short Answer
Answer each question in one or two complete sentences.
1. A pencil is 18 centimeters long. How many millimeters is that? Show your work.
Sample answer: There are 10 millimeters in 1 centimeter, so 18 × 10 = 180 millimeters. The pencil is 180 millimeters long.
A good answer includes: There are 10 millimeters in 1 centimeter, so 18 × 10 = 180 millimeters. The pencil is 180 millimeters long.
2. A suitcase weighs 15 kilograms. How many grams does it weigh? Explain your reasoning.
Sample answer: There are 1,000 grams in 1 kilogram, so 15 × 1,000 = 15,000 grams. The suitcase weighs 15,000 grams.
A good answer includes: There are 1,000 grams in 1 kilogram, so 15 × 1,000 = 15,000 grams. The suitcase weighs 15,000 grams.