Multiplying by 10 & 100
5. Which is another way to find 10+10+10?
What is 3 x 10
14. A gallon of paint can cover about 400 square feet of wall space. About how many square feet of wall space will 3 gallons cover?
What is 1,200 square feet
3. Which shows 1 way to use break apart to find 7 x 32?
What is (7x30)+(7x2)
2. There are 52 weeks in 1 year. If Jean turned 9 today, which is the best estimate of the number of months Jean has been alive?
What is 50 x 9= 450 months
7. Susanna's school received 4 boxes of books with 24 books in each box. Which is a reasonable estimate for the total number of books?
What is both 80 and 100
9. Write a number sentence that shows another way to find 100+100+100+100
What is 100 x 4
1. Mrs. Ortiz can make 50 tortillas out of 1 batch of dough. If she makes 4 batches, how many tortillas can she make?
What is 200
13. Use breaking apart to find the product for 6 x 135
What is 810
8. Ivan gets $22 a month for completing his chores. Use rounding to estimate the amount of money I van would have if he saved all the money for 6 months. Write a number sentence to show your work.
What is 20 x 6 = 120 months
19. Nia has 5 piles of paper clips. There are 79 paper clips in each pile. She says she has 3,995 paper clips in all. Is her answer reasonable? Why or why not?
What is No. 5 x 79 = 395, so her answer is too large
15. Find the product for 7 x 10
What is 70
16. Judy has 5 rolls of stamps. There are 100 stamps in each roll. How many stamps does she have?
What is 500 stamps
17. Raul is buying 3 shirts that cost $29 each. How much will the 3 shirts cost?
What is 87
18. Ricky saves $7 each week. Use rounding to estimate the amount he will have saved after 1 year. Write a number sentence to show your work.
11. Write an expression that uses breaking apart to find 5 x 17
What is (5x10) + (5x7)= 85