Multiplying Whole Numbers
Multiply. Show your work.
78 x 6
468
Write 103 in repeated multiplication and find the value.
10 x 10 x 10
1,000
Choose an equivalent expression.
7.4 x 1,000 =
a. 0.074 b. 740
c. 0.74 d. 7,400
7.4 x 1,000 = d. 7,400
Choose the closest estimate (without computing the actual product).
8,231 x 5
a. 40,000 b. 45,000
c. 35,000 d. 30,000
8,231 x 5 is about a. 40,000
Josphina saves $27 each week in January. She estimated that she will have have saved more than $100 in 4 weeks. Is Josphina's estimate reasonable? Explain how you can know without finding the actual amount. (You can find the actual amount if you need)
Josphina would save more than $100 in 4 weeks. If I estimate $27 to $30 and multiply by that by 4 weeks I would get $120 which over $100.
Multiply. Show your work.
6,718 x 4 =
26,872
Write the exponential form and find the value for:
10 x 10 x 10 x 10
104 = 10,000 = 10 x 10 x 10 x10
Choose an equivalent expression.
0.65 x 10 =
a. 6.5 b. 65
c. 0.650 d. 0.065
0.65 x 10 = a. 6.5
Choose the closest estimate (without computing the actual product).
7,188 x 2
a. 12,000 b. 16,000
c. 14,000 d. 20,000
7,188 x 2 is about c. 14,000
A zebra weighs 774 pounds. A Grizzle Bear weighs 0.14 times as much as the zebra. Does the zebra or grizzle bear weigh more? Explain how you know without finding the actual weight of the Grizzle Bear.
The zebra will weigh more. I know this because I would multiply the weight of the zebra 774 lbs by 0.14. I know if I did multiply these it would be smaller than 774 lbs because 0.14 is less than 1.
Multiply. Show your work.
9,276 x 8
74,208
Write the exponential form and repeated multiplication for 100
102 = 10 x 10 = 100
Choose an equivalent expression. 7 x 0.6 =
a. 0.6 x 0.6 x 0.6 x 0.6 x 0.6 x 0.6 x 0.6
b. 7 x 6
c. 7 x 6 x 0.1 x 10
d. 7 x 6 x 0.1
7 x 0.6 = d. 7 x 6 x 0.1
When you multiply 47.5 by 0.1, is the product greater than or less than 47.5? Explain.
The product (answer) will be less because you are multiplying by a decimal that is less than one.
**remember when we multiply by fractions our answers get smaller.
Heath weighs 28 pounds. Brooks weighs 3.4 times as much as Heath. Does Heath or Brooks weigh more? Explain how you know without actually finding the weight of Bruno.
Brooks would weigh more. I know this because if I did multiply 28 by 3.4 it would be greater than 28. The number 3.4 is greater than 1 whole.
Multiply. Show your work.
93 x 17 =
1,581
Write each product.
8 x 102 =
6 x 103 =
1. 8 x 102 = 800
1. 6 x 103 =6,000
Choose an equivalent expression. 3 x 0.09 =
a. 3 x 9 x 100
b. 3 x 9 x 0.1
c. 3 x 9 x 0.01
d. 0.9 x 0.9 x 0.9
3 x 0.09 = c. 3 x 9 x 0.01
When you multiply 8.17 by 0.01, is the product greater than or less than 8.17? Explain.
The product will be less than because you are multiplying a whole number by a decimal that is less than one.
Explain how you could use equivalent fractions or repeated addition to find the product of 0.7 x 4
0.7 + 0.7 + 0.7 + 0.7
Multiply. Show your work.
84 x 49 =
4,116
Write each product.
60 x 0.1 =
72 x 0.01 =
1. 60 x 0.1 = 6
2. 72 x 0.01 =0.72
The product 83 x 26 = 2,158. Complete the equations to show how you can use powers of ten to find the product of 83 x 0.26.
83 x 0.26 = 83 x (26 x ____)
83 x 0.26 = 2,158 x _____
83 x 0.26 = _____
83 x 0.26 = 83 x (26 x .01)
83 x 0.26 = 2,158 x 0.01
83 x 0.26 = 21.58
Select each expression that is equivalent to 3 x 10 x 10 x 10.
a. 3 x 1,000 b. 300 x 10 c. 3 x 102
d. 30 x 102 e. 3 x (3 x 10) f. 3 x 103
Select each expression that is equivalent to 3 x 10 x 10 x 10.
a. 3 x 1,000
b. 300 x 10
d. 30 x 102
f. 3 x 103
Explain how you could use equivalent fractions or repeated addition to find the product of 4 x 0.5
0.5 + 0.5 + 0.5 + 0.5