Estimating Decimals
Rounding Rules
The digit to the right is greater or equal to 5, round up
The digit to the right is less than 5, round down
Rounding Jingle
4 and less let it rest,
5 and up bump it up
Guided Practice
Round each decimal to the nearest whole number.
5.39 =
43.27 =
16.892 =
51.508 =
99.83 =
Guided Practice
Round each decimal to the nearest tenth.
57.16 =
38.891 =
3.1974 =
17.753 =
29.987 =
Guided Practice
Round each decimal to the nearest hundredths.
4.468 =
3.761 =
38.997 =
Guided Practice
Estimate each sum or difference.
3.96 + 8.31 =
9.67 – 3.81 =
5.75 + 4.04 =
11.2 – 9.67 =
Problem Solving
Camera film costs $3.99 a roll. Wes needs 3 rolls to take pictures of the class party. He has $15. Does he have enough money?
Yes
Problem Solving
Flowers cost $5.99 a dozen. Faye wants to buy 2 dozen flowers. She also wants to buy a balloon that cost $4.50. Faye has $20. Does Faye have enough money to buy everything she wants?
Yes
Problem Solving
Eric bought pretzels for $1.89, peanuts for $2.39, and popcorn for $0.99. How much did he spend in all?
Answer: $5.27
Problem Solving
A party is scheduled to last one hour. Mrs. Call wants to show a video that lasts between 10 to 15 minutes. About how much time will be left for other activities?
Answer: about 45-50 minutes