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Worksheet Grade 5 Math

Harkaway Landing Trash Boom: A Grade 5 Decimal Worksheet

A grade 5 worksheet adding, subtracting, multiplying, and dividing decimals using four weeks of trash weights from a fictional river boom's haul log.

Objectives

  1. Students will add and subtract decimals to hundredths by lining up the decimal points.
  2. Students will multiply a decimal by a whole number and divide a decimal by a whole number.
  3. Students will compare two decimals and explain the comparison using place value.

Vocabulary

Key words: boom, haul, decimal point, hundredths, place value

Teacher overview

Harkaway Landing is a fictional town on the Sable River, just upstream of the pipe that carries river water to the town's treatment plant. A floating barrier called a boom stretches across a slow bend above that pipe and catches bottles, foam, and branches before they reach the intake. A crew empties the boom once a week and weighs the haul on a platform scale, writing each weight in pounds and hundredths. The misconception this worksheet targets is judging a decimal by how many digits it has, so that a student reads 8.25 pounds as heavier than 8.5 pounds because 25 is greater than 5.

Harkaway Landing Trash Boom: A Grade 5 Decimal Worksheet — Grade 5 Math
Name: ____________________________ Date: ______________

Student Worksheet

The crew at Harkaway Landing weighs the trash the boom catches each week. Here is one month of the log.

Week 1 weighed 42.5 pounds. Week 2 weighed 38.75 pounds. Week 3 weighed 51.25 pounds. Week 4 weighed 46.5 pounds.

  1. What do Week 1 and Week 2 weigh together?
  2. What do Week 3 and Week 4 weigh together?
  3. What do all four weeks weigh together?
  4. How much more did Week 3 weigh than Week 2?
  5. The four weeks weigh 179 pounds in all. If every week had weighed the same, what would one week weigh?
  6. The crew carries the trash in bins. A full bin weighs 12.5 pounds. What do 6 full bins weigh?
  7. Each float on the boom weighs 3.25 pounds. What do 8 floats weigh?
  8. The boom is built from 4 sections. Each section weighs 18.6 pounds. What does the whole boom weigh?
  9. The crew starts with 50 pounds of rope and uses 18.65 pounds of it. How much rope is left?
  10. A haul of 8.5 pounds is heavier than a haul of 8.25 pounds. Explain how you know.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key
  1. Answer: 81.25 pounds.
    Line up the decimal points and add: 42.50 plus 38.75 = 81.25 pounds. Writing 42.5 as 42.50 keeps the hundredths column full.
  2. Answer: 97.75 pounds.
    Line up the decimal points and add: 51.25 plus 46.50 = 97.75 pounds.
  3. Answer: 179 pounds.
    Add the two totals already found: 81.25 plus 97.75 = 179.00 pounds. Adding all four weights in order gives the same result.
  4. Answer: 12.5 pounds.
    Subtract with the points lined up: 51.25 minus 38.75 = 12.50 pounds.
  5. Answer: 44.75 pounds.
    Divide the total by the number of weeks: 179 divided by 4 = 44.75 pounds. Checking, 44.75 x 4 = 179.
  6. Answer: 75 pounds.
    Multiply 12.5 x 6. Since 12 x 6 = 72 and 0.5 x 6 = 3, the product is 72 plus 3 = 75 pounds.
  7. Answer: 26 pounds.
    Multiply 3.25 x 8. Since 3 x 8 = 24 and 0.25 x 8 = 2, the product is 24 plus 2 = 26 pounds.
  8. Answer: 74.4 pounds.
    Multiply 18.6 x 4. Since 18 x 4 = 72 and 0.6 x 4 = 2.4, the product is 72 plus 2.4 = 74.4 pounds.
  9. Answer: 31.35 pounds.
    Write 50 as 50.00 and subtract: 50.00 minus 18.65 = 31.35 pounds.
  10. Answer: The 8.5-pound haul is heavier.
    Both hauls have 8 whole pounds, so the comparison happens in the tenths place. The first haul has 5 tenths and the second has only 2 tenths, and 5 tenths is more than 2 tenths. Writing 8.5 as 8.50 makes the two numbers easy to line up.

Differentiation

Support

Give these students grid paper with one column marked in bold for the decimal point, and have them rewrite every number with the same number of decimal places before they add or subtract. For items 6 through 8, provide the two partial products, such as 12 x 6 and 0.5 x 6, so students only have to add them.

Extension

Ask students to build a five-week log of their own in which the total is exactly 200 pounds, no two weeks are equal, and every weight is written to hundredths. Have them trade logs with a partner, who checks the total and finds what one week would weigh if the total were spread evenly.

ELL supports

Show a labeled photo or drawing of a floating boom on a river, with the words "boom," "float," "haul," and "scale" written in English and, where possible, in students' home languages. Provide a sentence frame for item 10: "8.5 is greater because it has ___ tenths and 8.25 has only ___ tenths."

Extensions

Have students weigh the trash their own class throws away over five school days, recording each weight to the nearest tenth of a pound. Ask them to find the five-day total, the amount one day would weigh if the total were shared evenly, and one sentence about which of those two numbers better describes a normal day.