Multiplication
30x40=
1200
Break 23 into tens and ones.
20 and 3
Estimate 19 x 31
20 x 30 = 600
Mr. Johnson's class started the year with 12 boxes of pencils. Each pack had 20 pencils. How many pencils did they have at the start of the school year?
240 pencils
What operation finds 15 groups of 24?
Multiplication
60x70=
4200
Find all partial products for 32 x 6 =
180, 12
About how much is 29 x 48
1,500
A teacher buys 24 packs of markers. Each pack has 32 markers. How many markers did the teacher
buy?
768 markers
Which equations are true?
50 x 30 = 1500 20 x 80 = 1800
20 x 40 = 8000 60 x 50 = 3000
50 x 30 = 1500
60 x 50 = 3000
24x13=
312
Find all partial products for 34 x 16
300, 40, 180, 24
Which is a better estimate for 37 x 22?
600 or 800
800
Keith practices soccer for 26 minutes each day for 18 days. Wesley practices twice as many minutes as Keith. How many minutes did Wesley practice?
936 minutes
Carter is going to buy two different apps for 10 months. One app costs $14 and the other app costs $19. Write an equation that can be used to find c, the total cost.
c = (12 +14) x 10
47x13=
611
Solve 42 x 23 using area model.
Show your work.
800 + 40 + 120 + 6 = 966
A deck of playing cards has 52 cards. About how many cards are in 45 decks?
2,500
Katie decorates two posters with stickers. The first poster needs 14 rows of 16 yellow stickers. The second
poster needs 12 rows of 15 red stickers. How many stickers will she use in all?
404 stickers
Ella is shopping for online gaming plans. She wants to sign up for 2 plans. She lists the monthly prices to compare services. Italian Bros $16 per month, Boxworld $13 per month, Vortex $17 per month
Write an equation to find s how much Ella will pay for one year of services for Boxworld and Vortex. Solve.
s = (16 +17) x 12
396
36x24=
864
Sadie made a mistake when she was using the area model to solve 37 x 42. These are the partial products that she came up with:120, 280, 60, 14
What mistake did she make? Fix it and solve the problem.
30 x 40 should be 1200 instead of 120.
37 x 42 = 1554
Carson loves the Mamba roller coaster so much that she’s ridden it 18 times!
Each ride lasts 79 seconds. She told her dad that she’s ridden the Mamba for a total of 2,492 seconds.
Does that sound about right? Use estimation to explain your answer.
No, 20 x 80 is 1600 so that is not very close to 2,492. Her answer is not reasonable.
When finding 44 × 21, Antonio says he knows 44 × 2 = 88 and 44 × 1 = 44. How could he use these facts to find 44 × 21?
Since the 2 in 21 is 2 tens. He could write a zero after 88. Then he could add 880 + 44 = 924
A store sells 16 cartons of milk with 24 bottles in each carton. The group will sell 175 more bottles tomorrow. A student writes this equation to find b, the total number of bottles:
b = (16 + 24) + 175
Explain the mistake and write a correct equation. Solve
The student added 16 and 24 instead of multiplying cartons by bottles per carton. Correct equation:
b = (16 × 24) + 175
b = 559