1. MATH UNIT 7
4th Grade

2. Arrays and Multiplying 2-Digit Numbers
How can you multiply using an array?
There are 13 trees in 24 equal rows.
How many trees are there?
4 x 10
10 x 20
3 x 4
3 x 20

3. Separate each factors into tens and ones.
What is another way to multiply 2-Digit numbers?
Draw a table.
Separate each factors into tens and ones.
Multiply to find partial products.
Add.
37 x 26 20 + 6

4. Find the product of 26 x 18 using partial products.

5. Find the product of 11 x 16 using partial products.

6. Use partial products to solve
19 x 27.

7. Complete the table to find the product.
18 x 25

8. Complete the tables to solve.
12 x 28
17 x 68
13 x 31
16 x 27
22 x 88
18 x 25

9. The prices at Dunn’s Store are shown
at the right. If 27 boxes of neon key
chains and 35 boxes of glow-in-the-dark
pens were purchased, what was the
total cost?
Item
Price per box
Neon key chains
$16
Glow-in-the-dark pens
$12

10. ? Seats in Section 200 The Florida Theatre in Jacksonville
has 1,918 seats in all. Section 200
has 27 rows with 14 seats in each
row. How many seats are in
Section 200?
? Seats in Section 200 14

11. Maggie is making a balloon game for the school fair. Kids will throw
darts at a 13 x 14 display to try
to pop the balloons.
How many balloons
are needed to set
up the game?

12. Maggie knows that she will have
to completely refill the balloon
board at least 15 times during the
day of the fair. Which expression
shows how to find the number of
balloons she will need?
15 x b. 15 x ( 13 x 14 )
c x d. 15 x ( )

13. Megan has d customers in her dog walking service. She walks
each dog once a day.
Which expression shows how many
dogs she walks in 12 weeks?
( d + 12 ) x b. 12 – ( d x 7 )
c. (d x 7 ) x d. ( 7 x 12 ) + d

14. The flagpole in front
of the school is 35
feet high. How many
inches tall is the
flagpole?

15. The Castillo de San Marcos is the
Spanish fortress in old St. Augustine,
Florida. I was built between and
Rounded to the nearest ten
thousand, how many pesos did it cost
to build the fortress at that time?
It cost 138,375
pesos to build
this fortress.

16. Find all of the partial products and then add to find the product.
2 3
X 1 4
4 1
X 2 5 + +

17. Find all of the partial products and then add to find the product.
3 4
X 5 1
7 3
X 8 1 + +

18. Find all of the partial products and then add to find the product.
6 4
X 3 2
2 6
X 5 3 + +

19. A pair of one type of shoes weighs 15 ounces. The shoebox
they come in weighs 2 ounces.
Which is the total weight in ounces
of 15 pairs of these shoes, including
the boxes?
a ounces
c ounces
b ounces
d ounces

20. Nikie estimated 23 x 43 by using Which method will give a closer
20 x 40. Rebecca estimated 23 x 43
by using 25 x 40.
Which method will give a closer
estimate and why?

21. How much shorter is Runway 5
Runway 3 at the Airport
is 13,000 feet long and
Runway 5 is 9,472 feet long.
How much shorter is Runway 5
than Runway 2?

22. Our school has two large patios. One is rectangular and is 24 feet
long by 18 feet wide.
The other is square and each
side is 21 feet long. Which patio has
the largest perimeter?
Which patio has the largest area?

23. Mrs. B buys 23 rock identification kits for her science lessons.
If each kit contains 28 rocks, how many
rocks are there in all?
Use the breaking apart method to solve.

24. Ryan’s class raised frogs from tadpoles. The class has
students and each raised 6
tadpoles. All but 6 of the tadpoles
grew to be frogs. Write a number
sentence to show how many
frogs the class has.

25. It took Sophie 45 minutes to clean her room. How many seconds
did it take her to clean her room?

26. How many fossil kits with 12 samples each have the same
number of fossils as 30 fossil
kits with 8 samples each?

27. One family of Florida scrub jays inhabits about 25 acres of land.
No other scrub jay families live
within this area. How many acres
of land do 24 families
of Florida scrub jays
need?
Endangered
species

28. A roller coaster runs rides 50 times an hour and reaches
speeds of 70 miles per hour.
Using the picture,
how many people can ride each hour?

29. Multiplying 2-Digit by 2-Digit A ferry carried an average of 37
cars per trip on Saturday. If the
ferry made 24 one-way trips, how
many cars did it carry?

30. The Queen Mary 2’s height above the
water is the same as a 23-story building.
If a single story is 11 feet tall, how high
above the water is the Queen Mary 2?

31. Alex bought sketch pads for all 23
students in his class. Each sketch pad
contained 50 sheets of paper.
How many sheets of paper were
there all together?

32. In 2005, an ultra light airplane tracked Monarch butterflies
migrating to Mexico. Over 13 days,
how many miles did the
butterflies travel?
Average distance
each day: 45 miles.

33. Two-Question Problems
Arianne and Autumn are preparing for a
bike race. On Wednesday, they rode their
bikes 32 miles in the morning and 22 miles
in the afternoon. How many miles did
they ride in all?
Arianne and Autumn biked the same
number of miles on Wednesday, Thursday,
Friday, and Saturday. How far did they ride
during the week?

34. Charlie used 3 rolls of film to take pictures on vacation. There were
pictures on each roll. How many
pictures did Charlie take.
Charlie had two copies made of
each picture. How many copies
were made?

35. Caroline buys a sandwich for $4, an apple for $1, and a drink for $2.
How much did she pay in all?
How much change did she receive
if she paid with a $20 bill?

36. Ethan and Jimmy mow their neighbors’ lawns
in the summer. Ethan mows 5 lawns each week. Jimmy mows three times as many
lawns as Ethan. How many lawns does
Jimmy mow each week?
Jimmy gets paid $20 for each lawn he mows.
How much does he get paid each week?

37. The Florida panther is known to sleep up to 18 hours each day.
About how many ours would
a Florida panther sleep in one
month?

38. Billy’s mom brought 3 bags of plain popcorn and 2 bags of caramel
popcorn to the park. How many
bags of popcorn did Billy’s mom
bring to the park?
Each bag of popcorn contained 16
servings. How many servings of popcorn
did Billy’s mom bring to the park?

39. Kay plans to retile her porch floor. She wants to buy 26 black tiles
and 23 white tiles. Each tile costs
$2. How much money will
It cost Kay to retile her porch?

40. How can you multiply with multiples of 10, 100, and 1,000?
The Ocean Water company produces
water bottles. If it made cases of
water in one day, how many water
bottles would it produce in all?
bottles
per case

41. To find the answer use the pattern: 8 x 30 = ___0 80 x 30 = ___00
What if each case holds 50 bottles?

42. When multiplying by multiples of basic fact followed by the number of
10, 100, 1000, the product is the
basic fact followed by the number of
zeros in both factors.
400 x 800
2000 x 700
6,000 x 5,000

43. basic fact followed by the number of
The product is the
basic fact followed by the number of
zeros in both factors.
60 x 2,000
500 x 300
7,000 x 3,000
40,000 x 2,000
120,000 x 9,000
8,000 x 6,000

44. The number of times that a heart beats each
minute is called the heart rate.
Smaller animals usually have higher heart
rates than large animals.
Find the heart beats per hour for each.
ELEPHANT 30
PIG 70
RABBIT
200
MOUSE
600

45. A hummingbird’s heart can beat About how many times does it
up to 1,260 times per minute.
About how many times does it
beat in 5 minutes?

46. The goal of Orange Street Elementary
was to collect 16,000 soup labels.
Did the school meet its goal if 20
classes collected labels each?
How many more or fewer labels
than 16,000 did the school collect?

47. How many zeros will be in the
product of 50,000 x 800,000?
_________
product of 900,000 x 90,000?

48. In one year a city recorded a total of 86 rainy days
In one year a city recorded a total of 86 rainy days. How many days did it NOT rain during that year?
365 86

49. William has saved $82. He wants to buy a new ripstick that costs
$163 and a helmet that costs $32.
How much more will he need
to save?

50. Estimation of Products
In 1991, NASA launched the Upper Atmosphere
Research Satellite (UARS).
It orbits Earth about times each week.
There are 52 weeks in one year.
About how many orbits does it make in
one full year?

51. Use rounding to estimate the number of orbits in one year.
52 x 105
52 x 100 = 5,200 or
Use compatible numbers
55 x 100 = 5,500
Remember: These are both ESTIMATES!

52. Solve by ESTIMATING! 324 x 93 716 x 106 425 x 62 846 x 491 834 x 21

53. Solve by ESTIMATING! 198 X 605 153 X 28 703 X 42 387 X 24 503 X 42

54. During one space mission, an American astronaut spent more
than hours in space. About
how many minutes did he spend
in space?