Add, Subtract and Estimate Decimals

Have your child rewrite each problem in columns with the points lined up, even when the page shows it across. Ask for an estimate first and compare it to the exact answer. Use the money pages if decimals feel abstract, then check every page with the answer key.

Estimate first, then add or subtract decimals and compare the answers. To check an answer, estimate first: round each number to the nearest whole number. The exact answer should be close to the estimate. The directions on the page read: Estimate first. Then, solve in the box and write the exact answer. The page opens with a worked example, and the answer key shows every answer.

Yes, both. We made it for 5th Grade decimals, and the page works the same whether it lands on a kitchen table or a center rotation. At home, most families go through it together and talk the answers out loud, and that talking is where most of the learning happens with adding and subtracting decimals. In class it runs well as independent work while you pull a small group. Print one copy or thirty, whichever the day needs.

Line up the decimal points so each place sits over the same place, write zeros in empty places (3.4 becomes 3.40), then add or subtract as with whole numbers and bring the point straight down.

When a top digit is too small, borrow 1 from the place to the left and add 10 to this place, just as with whole numbers. 6.2 - 2.47 is written as 6.20 - 2.47, and both the hundredths and the tenths need to regroup.

An estimate catches a misplaced point. 6.84 + 2.17 is about 7 + 2 = 9, so an answer of 90.1 or 0.901 is clearly wrong. The estimating pages round to the nearest whole number or tenth first.

They support CCSS 5.NBT.B.7, adding and subtracting decimals to hundredths using models, place value strategies and written methods.

5th graders read, write, compare and round decimals to thousandths (CCSS 5.NBT.A.3 and 5.NBT.A.4), understand place value patterns and powers of 10 (5.NBT.A.1 and 5.NBT.A.2), and add, subtract, multiply and divide decimals to hundredths (5.NBT.B.7).

Start with place value to thousandths, then comparing, ordering and rounding. Move to adding and subtracting, then multiplying and dividing. Finish with word problems, mixed operations and a unit review. The subtopics on this page follow that order.

Estimate first. Rounding each number to a whole number gives a ballpark answer, so 4.8 x 3.1 should be about 15, which rules out 1.488 and 148.8.

Yes. All 55 sheets have an answer key, and the two page sheets have a two page key.