Estimating
Round to the nearest ten, then multiply.
23 x 28
600
Rewrite the expression using the distrubtive property:
56 x 84 =
(____+____) x (____ + ____)
(50 + 6) x (80 + 4)
A baker makes 24 trays of cookies. Each tray has 36 cookies.
How many cookies did the baker make in all?
24 × 36 = 864 cookies
List all the partial products for
23 × 45
800, 100, 120, 15
The product of two factors is 600.
One factor is 30. What is the other factor?
20
Round to the nearest ten, then multiply.
65 x 19
1,400
Which expressions equal 240?
A. (20 × 12)
B. (30 × 8)
C. (24 × 10)
D. All of the above
D.
There are 45 students in each grade at a school. There are 12 grades in the school.
How many students are there in the school altogether?
45 × 12 = 540 students
List all the partial products for
56 × 21
1,000, 50, 120, 6
The product of two factors is 1,200.
One factor is 20. What is the other factor?
60
Which estimate is more reasonable for 48 × 22?
A. 40 × 20 = 800
B. 50 × 20 = 1,000
C. 50 × 30 = 1,500
D. 40 × 30 = 1,200
B. 1,000
Which expression shows 23 × 6 using the distributive property?
A. (20 × 6) + (3 × 6)
B. (23 × 3) × 2
C. (23 + 6) × 1
D. (20 × 3) + (6 × 3)
A
A store stacks 28 boxes on each pallet. There are 34 pallets in the warehouse.
How many boxes are there in total?
28 × 34 = 952 boxes
List all the partial products for
34 × 62
1,800, 60, 240, 8
A number multiplied by 40 equals 2,400.
What is the missing factor?
60
A theater has 88 rows with 26 seats in each row.
Which estimate is most reasonable?
A. 2,800 seats
B. 2,100 seats
C. 3,600 seats
D. 2,700 seats
D. 2,700 seats
Is (20 × 7) + (4 × 7) equal to 24 × 7?
Yes
A carnival sets up 36 booths. Each booth sells 48 tickets.
Later in the day, the carnival sets up 14 more booths, and each of those booths also sells 48 tickets.
How many tickets are sold in all?
2,400 tickets
Which is the greatest partial product of 92 x 38?
2,700
The product is 3,200. One factor is 80.
What is the other factor?
40
A school orders 38 boxes of pencils. Each box has about 24 pencils.
Which estimate is most reasonable?
A. 40 × 20
B. 30 × 20
C. 40 × 30
D. 30 × 30
A. 40 x 20
Which two expressions equal 420?
A. 42 x 10
B. 40 x 10 + 2
C. 40 x 10 + 2 x 10
D. 40 x 10 + 20 x 10
A and C
Painting 2; 112 feet
Which is NOT a partial product of 58 × 46?
A. 2,000
B. 3,000
C. 320
D. 48
B.
A factory makes 4,500 items in 50 batches.
How many items are in each batch?
90 items