Addition/Subtraction
Rounding
Algorithm
100

Eli is going on a vacation and buys pretzels and carrots to bring in the car. The pretzels weigh 314 grams, and the carrots weigh 453 grams. What is the difference between the weight of the pretzels and the carrots?

139 grams

100

Sarai drinks about 115 L of water in one month. 

Round to the nearest ten how many liters of water Sarai drinks in one month.

120L of water.

100

64 +29=

93

200

At birth a horse weighs about 68 kilograms. An average adult horse weighs about 571 kilograms. How much weight does a horse gain from birth to adult?

503 kilograms

200

When driving, Mrs. Bower uses 56 L of fuel every minute. 

 Round to the nearest ten liters to estimate how many liters of fuel get used every minute

60L

200

435+186=

621

300

There are 75 students in Grade 3. There are 47 more students in Grade 4 than in Grade 3. How many students are in Grade 4?

112 students.

300

Lindsey is making desserts for her party.

A cupcake recipe needs

150 grams of sugar. A pie recipe needs 135 grams of sugar.

Estimate how many grams of sugar Lindsey will need to make cupcakes and a pie, by rounding to the nearest 10.

290 grams

300

183-37=

146

400

There are 384 boys at Lake Cormorant Elementary School and 416 girls. How many more girls attend Lake Cormorant Elementary School than boys?

32

400

Lindsey is making desserts for her party.

A cupcake recipe needs

150 grams of sugar. A pie recipe needs 135 grams of sugar.

Estimate how many grams of sugar Lindsey will need to make cupcakes and a pie, by rounding to the nearest 100.

300 grams

400

300-72=

228

500

Caiden has 457 pennies in a jar. He also has 372 pennies in a piggy bank. How many pennies does he have in all?

829 pennies

500

Jimmy and Maria are saving up for a new television and Nintendo Switch. They found a television at Best Buy for $245 and the Nintendo Switch for $317. Jimmy says they need to save about $500 to buy the television and the Nintendo Switch. Maria says they need to save about $600. 

Who do you agree with? Why

Jimmy245 rounds to 200 and 317 rounds to 300.

200+300=500

500

427-289

138