To add or subtract, line up the points and work as with whole numbers. To multiply or divide, work as with whole numbers, then place the point so the answer fits an estimate.
decimal pointthe dot between the ones and tenths
tenthsthe first place after the point
hundredthsthe second place after the point
estimatea close guess to check the answer
Watch for: Lining up the last digits instead of the points, as in 2.5 + 1.25. Putting the point in the wrong spot: 4.3 × 2 is 8.6, not 86. Dropping the point when dividing: 7.8 ÷ 3 is 2.6, not 26.
At home: Add up a few prices from a receipt or menu on paper, lining up the points. Then check your total against the receipt.
Sample sheet and answer key
Luna's Space Adventure
Grade 5 · Decimal operations · 5.NBT.B.7
NameDate
Astronaut Luna is exploring a far-off corner of space. Solve each problem to help Luna's mission go smoothly!
Line up the points
Add or subtract like whole numbers, then drop the point straight down.
Nova spends $1.64 on paint and $2.08 on brushes. How much is that altogether?
1.64 + 2.08 = 3.72
3.72dollars
Answer key
New problems every time, three levels (gentle, core and stretch), themes to pick from, a second page if you want one. Each sheet comes with an answer key and a one-page guide for grown-ups.
