Halloween
Jane walked 13 miles trick or treating on Halloween. Cindy walked 18 miles trick or treating on Halloween. Approximately how many miles were walked by both girls?
What is 30 miles?
Justification: Estimate by 10, so round down to 10 for 13 and round 18 up to 20 to get 30
Betty sold 48 pastries on Thursday and 211 on Friday. What is the exact number of pastries that Betty sold on Thursday and Friday?
What is 269 pastries?
Justification: Solve by adding both numbers together because it is asking for exact amount.
Maria wants to buy a Halloween costume. She put $29 in her account last week and $9 in her account this week. Maria has about how much money now?
What is $40?
Justification: Round $29 up to $30 and round $9 to $10 to get $40.
Roger needs 23 cupcakes to give his class. He needs 43 cupcakes to give to his chess club. How many cupcakes does Roger need to make altogether?
What is about 46 cupcakes?
Justification: Solve by adding both numbers because it asks for how many altogether.