Students can use the **Spectrum Math Grade 3 Answer Key Chapter 10 Posttest** as a quick guide to resolve any of their doubts.

## Spectrum Math Grade 3 Chapter 10 Posttest Answers Key

**Check What You Learned**

**Complete the pattern by using addition or subtraction.**

Question 1.

1Â Â Â 2Â Â Â 3Â Â Â

Answer:

Generate the pattern 1 2 3 by using the simple addition with the given numbers by Adding 1 for the given series up to the number 7 which is as shown below.

Question 2.

50Â Â Â 45Â Â Â 40Â Â Â

Answer:

Generate the pattern 50 45 40 by using the simple addition with the given numbers by Subtracting 5 for the given series up to the number 20 which is as shown below.

Question 3.

100Â Â Â 90Â Â 80Â Â Â

Answer:

Generate the pattern 100 90 80 by using the simple Subtraction with the given numbers by Subtracting 10 for the given series up to the number 40 which is as shown below.

Question 4.

4Â Â Â Â Â 8Â Â Â Â 12Â Â Â

Answer:

Generate the pattern 4 8 16 by using the simple addition with the given numbers by Doubling the given series up to the number 256 which is as shown below.

Question 5.

2Â Â Â Â 4Â Â Â Â Â 6Â Â Â

Answer:

Generate the pattern 2 4 6 by using the simple addition with the given numbers by Adding 2 for the given series up to the number 14 which is as shown below.

Question 6.

33Â Â Â 35Â Â Â Â 37Â Â Â

Answer:

Generate the pattern 30 26 22 by using the simple addition with the given numbers by Adding 2 for the given series up to the number 6 which is as shown below.

**Write the number sentence. For the missing part, use a box (). Solve each number sentence.**

Question 7.

Twelve divided by six is what number? _____________

Twelve divided by six is _____________.

Answer:

Let the unknown number be x

GivenÂ 12 Ã· 7 =Â x =?

It implies x = 12 Ã· 7

x = 5

Therefore , When Twelve is divided by Six is 5.

Question 8.

Seven times three is what number? _____________

Seven times three is _____________.

Answer:

Given number is 7

When 7 is multiplied with 3 i.e. 7 x 3 = 21

Therefore , Seven times three is twenty one.

Question 9.

Five plus six is what number? _____________

Five plus six is _____________.

Answer:

Given 5 + 6 = ?

Let the unknown number be x.

When 5 and 6 are added x = 5 + 6 = 11

Therefore, Five plus Six is Eleven.

Question 10.

This number divided by four equals eight. _____________

_____________ divided by four equals eight.

Answer:

Let the unknown number be x

x Ã· 4 = 8

This implies , x = 8 x 4

x = 32

Therefore 32 is divided by four Equals eight.

Question 11.

Nine times this number equals seventy-two. _____________

Nine times _____________ equals seventy-two.

Answer:

Let the unknown be p

9 times p = 72

This implies p = 72 Ã· 9

p = 8

Therefore, Nine times 8 equals seventy-two.

Question 12.

Twelve times five equals what number? _____________

Twelve times five equals _____________.

Answer:

Let the unknown number be n

Given twelve times five = n =Â ?

12 x 5 = n

60 = n

Therefore , Twelve times five equals to sixty.

**Complete the following.**

Question 13.

a. 5 + ___________ = 5

Answer:

Try to implement the Addition identity as shown below

5+ 0 = 5 . When 5 and zero are added , the result is 3.

b. _________ + 0 = 4

Answer:

Try to implement the Addition identity as shown below

0+ 4 = 4 . When Zero and 4 are added , the result is 3.

c. 2 Ã— 1 = ___________

Answer:

Try to implement the Multiplication identity as shown below

2 x 1 = 2. When 2 and 1 are Multiplied , the result is 2.

d. 3 Ã— 1 = ____________

Answer:

Try to implement the Multiplication identity as shown below

3 x 1 = 3. When 3 and 1 are Multiplied , the result is 3.

Question 14.

a. 2 + 7 = 9 or

2 + 7 = 6 + _____________

Answer:

Try to implement the Commutative Addition property as shown below

2 + 7 = 9 or

2 + 7 = 6 + 3

b. 5 + 9 = 14 or

5 + 9 = 8 + ______________

Answer:

Try to implement the Commutative Addition property as shown below

5 + 9 = 14 or

5 + 9 = 8 + 6

c. 3 Ã— 8 = 24 or

3 Ã— 8 = 4 Ã— _____________

Answer:

Try to implement the Commutative Multiplication property as shown below

3 Ã— 8 = 24 or

3 Ã— 8 = 4 Ã— 8

d. 6 Ã— 2 = 12 or

6 Ã— 2 = 4 Ã— ______________

Answer:

Try to implement the Commutative Multiplication property as shown below

6 Ã— 2 = 12 or

6 Ã— 2 = 4 Ã— 3

Question 15.

a. 3 Ã— 2 Ã— 3 = y

3 Ã— 2 = 6

6 Ã— 3 = _____________

y = ____________

Answer:

Given 3 x 2 x 3 = x

According to the Associative property

3 Ã— 2 = 6

6Ã— 3 = 18

y = 18

Hence the Resultant value obtained after Simplification is y = 18

b. 4 Ã— 1 Ã— 2 = z

4 Ã— 1 = 4

4 Ã— 2 = _____________

z = _____________

Answer:

Given 4 x 1 x 2 = z

According to the Associative property

4 Ã— 1 = 4

4 Ã— 2 = 8

z = 8

Hence the Resultant value obtained after Simplification is z = 8

c. 2 Ã— 3 Ã— 6 = m

2 Ã— 3 = 6

6 Ã— 6 = _____________

m = ____________

Answer:

Given 2 x 3 x 6 = m

According to the Associative property

2 Ã— 3 = 6

6 Ã— 6 = 36

m = 36

Hence the Resultant value obtained after Simplification is m = 36

Question 16.

a. 2 Ã— 3 Ã— 8 = a

_____________ Ã— ____________ = ____________

_____________ Ã— ____________ = ____________

a = _____________

Answer:

Given 2 x 3 x 8 = a

According to the Associative property

2Ã— 3 = 6

6 Ã— 8 = 48

a = 48

Hence the Resultant value obtained after Simplification is a = 48

b. 1 Ã— 2 Ã— 7 = c

_____________ Ã— ____________ = ____________

_____________ Ã— ____________ = ____________

a = _____________

Answer:

Given 1 x 2 x 7 = c

According to the Associative property

1 Ã— 2 = 2

2 Ã— 7 = 14

c = 14

Hence the Resultant value obtained after Simplification is c = 14

c. 1 Ã— 5 Ã— 6 = k

_____________ Ã— ____________ = ____________

_____________ Ã— ____________ = ____________

a = _____________

Answer:

Given 1 x 5 x 6 = k

According to the Associative property

5 Ã— 6 = 30

30 Ã— 1 = 30

k = 30

Hence the Resultant value obtained after Simplification is k = 30

Question 17.

13 Ã— 7 = (10 Ã— 7) + (________ Ã— 7)

____________ + _____________ = ____________

Answer:

Given 13 Ã— 7 = (10 Ã— 7) + (________ Ã— 7)

According to the distributive property

13 Ã— 7 = (10 Ã— 7) + (Â 3Ã— 7)

70 + 21Â = 91

13 x 7 = 91

Hence the Resultant value obtained after Simplification is 91.

Question 18.

16 Ã— 6 = (10 Ã— 6) + (_________ Ã— 6)

_____________ + ____________ = ____________

Answer:

Given 16 Ã— 6 = (10 Ã— 6) + (________ Ã— 6)

According to the distributive property

16 Ã— 6 = (10 Ã— 6) + ( 6 Ã— 6)

60 + 36Â = 96

16 x 6 = 96

Hence the Resultant value obtained after Simplification is 91.

Question 19.

18 Ã— 4 = (10 Ã— 4) + (__________ Ã— 4)

___________ + ____________ = _____________

Answer:

Given 18 Ã— 4 = (10 Ã— 4) + (Ã— 4)

According to the distributive property

18 Ã— 4 = (10 Ã— 4) + (8 Ã— 4)

40 +32Â = 72

18 x 4 =72

Hence the Resultant value obtained after Simplification is 72.