Estimation
A student wants to estimate 31 x 48. What is the best estimate?
30 x 50 = 1,500
what is 40 x 30?
1,200
53 x 35
1,855
There are 34 paint brushes in one kit. How many paint brushes are in 47 kits?
1,598
Use partial products to solve: 12 × 14
What are the partial products?
100, 40, 20, 8
Estimate 62 x 19
60 x 20 = 1,200
What number makes the equation true? 800 x ____ = 40,000
50
16 x 76
1,216
Tickets cost $26 each. If 144 seats are sold, how much money is collected?
$3,744
Use partial products to solve: 23 × 15
What is the first partial product when multiplying 20 × 10?
200
Estimate 87 x 22.
90 x 20 = 1,800
What is 60 x 700?
42,000
44 x 38
1,672
Rachel reads 50 minutes each day. How many minutes does she read in 80 days?
4,000 minutes
Find the missing partial product.
34 × 27
(30 × 20) = 600
(30 × 7) = 210
(4 × 20) = 80
(4 × 7) = ?
28
Which estimate is closest to 54 x 38?
a. 60 x 30 = 1,800
b. 50 x 40 = 2,000
c. 60 x 40 = 2,400
d. 50 x 30 = 1,500
50 x 40 = 2,000
What is 23 x 30 ?
690
670 x 81
54,270
A teacher makes 176 booklets. Each booklet has 18 pages. How many pages are copied?
3,168 pages
Use partial products to solve: 42 × 36
What is the total of all partial products?
1,200 + 180 + 120 + 18 = 1,512
A school buys 79 boxes with 61 pencils in each box. Estimate the total number of pencils.
80 x 60 = 4,800
What is 90 x 80?
7,200
867 x 41
A warehouse ships 128 boxes. Each box contains 24 notebooks. How many notebooks are shipped?
3,072 notebooks
A student used partial products to solve 46 × 32.
40 × 30 = 1,200
40 × 2 = 80
6 × 30 = 180
6 × 2 = 12
1,200 + 80 + 180 + 12 = 1,382
The student made an error. What is the error, and what is the correct product.
The partial products are correct, but the student added them incorrectly.
1,200 + 80 + 180 + 12 = 1,472