Subtracting mixed numbers: 4th grade math lesson

What this lesson shows

3 1/4 − 1 3/4: trade a whole for 4/4 first.

The worked example

The lesson works this one step by step: 3 1/4 − 1 3/4. Then your kid tries one like it on paper.

The steps

Enough parts?
Trade a whole for parts
Subtract the parts
Subtract the wholes

Helping at home

Look at the parts first. If there are not enough to take away, trade 1 whole for its parts: 1 whole is 4 fourths. Then subtract the parts, then the wholes.

If your kid gets stuck

Enough parts to take away? If not, trade a whole.

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 4.NF.B.3c
Add and subtract mixed numbers with like denominators, e.g., by replacing each mixed number with an equivalent fraction, and/or by using properties of operations and the relationship between addition and subtraction.

Matches a standard in all 50 states and DCSee each state's code

Alabama MA19.4.15b
Alaska 4.NF.3.c
Arizona 4.NF.B.3.c, 4.NF.A.2.b
Arkansas 4.NPV.5, 4.CAR.5
California 4.NF.B.3
Colorado 4.NF.B.3.c
Connecticut 4.NF.B.3
Delaware 4.NF.B.3
District of Columbia 4.NF.B.3
Florida MA.4.FR.2.2
Georgia 4.NR.4.3, 4.NR.4.4, 4.NR.4.6, 5.NR.3.2
Hawaii 4.NF.B.3
Idaho 4.NF.A.2.b, 4.NF.B.3.c
Illinois 4.NF.B.3
Indiana 5.NS.1, 4.CA.7, 4.CA.6
Iowa 4.NF.A.2, 4.NF.B.3.c
Kansas 4.NF.3.c
Kentucky KY.4.NF.3.b, KY.4.NF.3.c, KY.4.NF.2
Louisiana 4.NF.B.3.b, 4.NF.B.3.c
Maine 4.NF.B.3c
Maryland 4.NOS.D.10.a, 4.NOS.E.12.c
Massachusetts 4.NF.B.3.c
Michigan 4.NF.B.3
Minnesota 4.1.2.2, 4.1.2.3, 5.1.2.3
Mississippi 4.NF.3.c
Missouri 4.NF.A.3, 4.NF.B.6, 5.NF.A.3
Montana MT.4.NF.3.a, MT.4.NF.3.c, 4.D1.2, 4.D1.25, 4.D2.6, 4.D4.1, 4.D5
Nebraska 4.N.2.a, 4.N.2.c, 4.N.3.b, 4.N.3.c, 5.N.2.b
Nevada 4.NF.B.3
New Hampshire 4.NF.B.3
New Jersey 4.NF.B.3c
New Mexico 4.NF.B.3
New York NY-4.NF.2, NY-4.NF.3.c
North Carolina NC.4.NF.3.c, NC.4.NF.3.d
North Dakota 4.NO.NF.2, 4.NO.NF.5
Ohio 4.NF.3.c
Oklahoma 4.N.3.2, 4.N.3.3, 4.N.3.5, 5.N.1.3
Oregon 4.NF.A.2, 4.NF.B.3
Pennsylvania CC.2.1.4.C.2
Rhode Island 4.NF.B.3.a, 4.NF.B.3.c
South Carolina 4.NR.2.4, 4.NR.2.6, 5.NR.2.1, 4.PAFR.2.1, 3.NR.2.4, 4.NR.2.5
South Dakota 4.NF.B.3.c
Tennessee 4.NF.A.2, 4.NF.B.3.c
Texas 111.6.b.3.A, 111.6.b.3.D, 111.6.b.3.E, 111.6.b.3.F, 111.6.b.3.G
Utah 4.NF.3.c
Vermont 4.NF.B.3
Virginia 3.NS.3b, 3.NS.3c, 3.NS.3e, 4.NS.3a, 4.NS.3b, 4.NS.3c, 4.NS.3d, 4.CE.3a
Washington 4.NF.B.3
West Virginia M.4.14
Wisconsin M.4.NF.A.2, M.4.NF.B.3
Wyoming 4.NF.2a, 4.NF.2b, 4.NFP.2.A, 4.NFP.2.B, 4.NF.3c, 4.NFP.3.C

Subtracting mixed numbers