Bigger or smaller, without computing: 5th grade math lesson

What this lesson shows

7 × 4/5 is less than 7, 7 × 5/4 is more than 7, and 7 × 5/5 is 7. Compare the fraction with 1.

The worked example

The lesson works this one step by step: 7 × 4/5. Then your kid tries one like it on paper.

The steps

Less than 1: smaller
More than 1: bigger
Equal to 1: the same

Helping at home

Do not multiply. Compare the fraction with 1 whole. Less than 1 makes the number smaller, more than 1 makes it bigger, and exactly 1 keeps it the same.

If your kid gets stuck

Write <, >, or =. Compare the fraction with 1.

Watch it with Lux

With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.

See how Lux works

Standards

Common Core 5.NF.B.5a
Comparing the size of a product to the size of one factor on the basis of the size of the other factor, without performing the indicated multiplication.
Common Core 5.NF.B.5b
Explaining why multiplying a given number by a fraction greater than 1 results in a product greater than the given number (recognizing multiplication by whole numbers greater than 1 as a familiar case); explaining why multiplying a given number by a fraction less than 1 results in a product smaller than the given number; and relating the principle of fraction equivalence a/b = (n × a)/(n × b) to the effect of multiplying a/b by 1.

Matches standards in 42 statesSee each state's code

Alabama MA19.5.13a, MA19.5.13b, MA19.5.13c
Alaska 5.NF.5.a, 5.NF.5.b
Arizona 5.NF.B.5.a, 5.NF.B.5.b
Arkansas 5.NPV.6
California 5.NF.B.5
Colorado 5.NF.B.5.a, 5.NF.B.5.b
Connecticut 5.NF.B.5
Delaware 5.NF.B.5
District of Columbia 5.NF.B.5
Florida MA.5.FR.2.3
Georgia 5.NR.3.5
Hawaii 5.NF.B.5
Idaho 5.NF.B.5.a, 5.NF.B.5.b
Illinois 5.NF.B.5
Iowa 5.NF.B.5.a, 5.NF.B.5.b
Kansas 5.NF.5.a, 5.NF.5.b
Kentucky KY.5.NF.5.a, KY.5.NF.5.b
Louisiana 5.NF.B.5.a, 5.NF.B.5.b, 5.NF.B.5.c, 5.NF.B.5.d
Maine 5.NF.B.5a, 5.NF.B.5b
Maryland 4.NOS.E.13.a, 5.NOS.D.11.a, 5.NOS.D.12.a, 5.NOS.D.13.a, 5.NOS.D.14.a, 5.NOS.D.14.b
Massachusetts 5.NF.B.5.a, 5.NF.B.5.b
Michigan 5.NF.B.5
Mississippi 5.NF.5a, 5.NF.5b
Missouri 5.NF.B.4, 5.NF.B.5.a, 5.NF.B.5.b, 5.NF.B.5.c, 5.NF.B.5.d
Montana MT.5.NF.5.a, MT.5.NF.5.b, 5.D1.14, 5.D4.5
Nevada 5.NF.B.5
New Hampshire 5.NF.B.5
New Jersey 5.NF.B.5a, 5.NF.B.5b
New Mexico 5.NF.B.5
New York NY-5.NF.5.a, NY-5.NF.5.b
North Carolina NC.5.NF.4.b
North Dakota 5.NO.NF.2
Ohio 5.NF.5.a, 5.NF.5.b
Oregon 5.NF.B.5
Rhode Island 5.NF.B.5.a, 5.NF.B.5.b
South Dakota 5.NF.B.5.a, 5.NF.B.5.b
Tennessee 5.NF.B.5.a, 5.NF.B.5.b
Utah 5.NF.5.a, 5.NF.5.b
Vermont 5.NF.B.5
Washington 5.NF.B.5
West Virginia M.5.15
Wisconsin M.5.NF.B.5

Bigger or smaller, without computing