Area Model and Partial Products
Use the area model to solve
345 X 7
2,415
What is the most reasonable estimate for 68 X 221?
a. 60 X 300
b. 600 X 200
c. 70 X 200
d. 700 X 300
C. 70 X 200
Which are equivalent to 104
a. 10X4
b. 10X10X10X10
c. 1,000
d. 10,000
B and D
Is this product correct? If not, where did they make the mistake? What is the correct answer?
178 X 4 = 482
No. They didn't add 3 from 32 when they multiplied 4X7 and they didn't add 3 from 31 when they multiplied 4X1. It should be 712
A bus company charges $83 for a ride from one city to another. During the last trip, the bus had 42 fares. How much money did the bus company earn?
$3,486
Use the area model to solve 45 X 8
360
A rectangular field measures 416 feet wide by 52 feet long. About how much is the area of the field?
400 X 50 = 20,000
A square has a side length of 10. Which could represent the area of the square?
a. 10 X 2
b. 10 X 10
c. 10 + 10 + 10 +10
d. 100
B and D
Is this product correct? If not, where did they make the mistake? What is the correct answer?
397 X 9 = 2,382
it is correct
In it's frame, a rectangular poster measures 68 inches long and 45 inches wide. How much wall space does the poster cover?
68X45 = 3,060 inches
Use partial products to multiply 64 X 538
30,000
1800
480
2000
120
+ 32
34,432
The total in multiplication.
Product
What number is equivalent to 38 X 105
3,800,000
Is this product correct? If not, where did they make the mistake? What is the correct answer?
513 X 25 = 3591
No they are not correct. They forgot to add a 0 when they started multiplying by 2 in the tens place. The answer is 12,825. If they would have estimated first they would have noticed they made a mistake.
The average attendance at a town's high school soccer games is 4,153 people per (at each) game. How many people attend the teams 8 home games this season. Given an estimate and the exact number.
Estimate 4,000 X 8 = 32,000
Actual 4,153 X 8 = 33,224 people at the home games this season.
Solve 46 X 28 with an area model and the standard algorithm. Which method do you prefer and why?
1,288
Why does estimating help you in multiplication?
It helps me check to make sure I didn't make a mistake because my product should be close to the actual product. It is also helpful when shopping so I can get close to the total.
What exponent completes the equation?
42 X ________ = 420,000
104
A theatre has 1,475 seats. For a show's 39 performances every seat was filled. How many people saw the show?
57,525
Words that indicate you should multiply in word problems
each, per, equal groups, how many