You line up the decimals and then add the numbers.
100
58.9 + 3.04 =
61.94
100
3.95 - 2.7 =
1.25
100
.6 x 2.1 =
1.26
100
Alan is connecting three garden hoses to make one longer hose. The green hose is 6.25 feet long, the orange hose is 5.755 feet long, and the black hose is 6.5 feet long. What is the total length of the hose?
18.505
200
How do you subtract decimals?
You line up the decimals and then subtract the numbers.
200
.004 + 5.1 =
5.104
200
95.29 - 1.3 =
93.99
200
4.25 x 21 =
89.25
200
The average length of a humpback whale is 13.7 meters. The average length of a killer whale is 6.85 meters. How much longer is the humpback whale than the killer whale?
6.85 meters
300
What do you do if there are not enough digits in the top number to subtract a problem?
You have to add on zero's.
300
.9843 + 2.67 =
3.6543
300
125 - .68 =
124.32
300
.03 x .03 =
.0009
300
A pen costs $1.38. The sales tax is 0.06 of the cost. What is the amount of sales tax?
$0.08
400
How do you multiply decimals?
You multiply the numbers and then you count how many spaces there are to the right of the decimals and count them over to the left in the answer.
400
5 + 2.78 + .030 =
7.81
400
.468 - .059 =
.409
400
2.003 x .05 =
.10015
400
A classified ad costs $2.45 per line per day. How much will it cost to run a 4-line ad for 7 days?
$68.60
500
How do you divide decimals?
You have to get rid of the decimals on the outside by moving the decimals on the inside. Then bring the decimal straight up and divide normally.
500
8.07 + .0976 + 23.3 + 48 =
79.4676
500
5.45 - 3.799 =
1.651
500
.312 x 1.67 =
.52104
500
Ms. Blox bought 6 pounds of hamburger at $1.88 per pound and a bag of potatoes for $1.35. How much did she spend in all?