4.1 Multiply by Tens
80 x 10 = _________
800
27 x 50 = _____
1,500
15 x 67 = _______
1,005
Compare
40 x 10 ____ 400
What sign must be there?
=
A farmer has 59 cows. Each cow produces 27 liters of milk. How many liters of milk do the cows produce in all?
1,593 liters
60 x 50 = _______
3,000
63 x 72 = ________
4,200
26 x 51 = ______
1,326
Compare
8 x 70 ____ 5,600
What sign must be there?
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A jeweler has 46 ring pillows. Each pillow has 3 rows with 6 rings in each row. How many rings are there in all?
3 x 6 = 18
18 x 46= 828 rings
90 x 90 = _____
8,100
48 x 36
2,000
43 x 18= _____
774
Compare
50 x 60 _____ 300
What sign must be there?
>
A music fan memorizes 59 songs for a concert. Her goal is to memorize all of the songs from 13 albums. There are 15 songs on each album. How many more songs does the music fan still need to memorize?
136 songs
32 × 20 = _____
640
57 x 38 = ______
60 x 40 = 2,400
44 x 68 = _____
2, 992
Without calculating exactly, decide which product is greater:
29 x 27 or 21 x 29
29 x 27 = around 30 x 26 = 780
21 x 29 = around 20 x 30 = 600
A pet store receives a shipment of 5 boxes of cat treats. Each box is 30 inches high and has 16 bags of cat treats. Each bag has 32 ounces of cat treats. How many ounces of cat treats does the pet store receive in the shipment?
32 x 16 = 512
512 x 5= 2,560
2,560 ounces
18 × 30 =______
540
You use 25 × 30 to estimate 26 × 31. Will your estimate be greater than or less than the actual product?
less than
29 x 92= _______
2,668
A shop sells 49 pencils in one box. A school orders 27 boxes.
Instead of multiplying directly, use the distributive property to calculate the total number of pencils.
49 x 27 = 50 x 27 - 27 = 1323
If you and Rajiv each meet your goal each week, how many more hours will you exercise in 1 year than Rajiv?
Rajiv exercises 4 hours a week, while you exercise 10 hours a week.
*hint: there are 52 weeks in a year*
4 x 52 = 208 (Rajiv)
10 x 52 = 520 (You)
520-208= 312 hours
312 hours