7th Grade Math

Text Option Take the Quick Check below. Refer to the Quick Review for help.

You have two options for checking

prerequisite skills for this chapter.

428 Probability and Predictions

Find each value.

1. 
   

   7 × 15 2. 24 × 6

   
   


2. 
   

   13 × 4 4. 8 × 21

   
   


3. 
   

   6 × 5 × 4 × 3 6. 4 × 3 × 2 × 1

   
   


4. 
   

   10 × 9 × 8 × 7 8. 11 × 10 × 9

   
   


5. 
   

   3 6 × ×^52 10. 5 9 ××^8 4 ××^7 3

   
   


6. 
   

   _ 3 4 × ×^3 2 × ×^21 12. __^7 4 ××^6 3 ×× (^5 2) ××^4 1

   
   


7. 
   

   MUSIC If you download 9 songs an
   hour for 5 hours every day this week,
   how many songs will you have
   downloaded this week?

   
   

EXAMPLE 1

Find 7 × 6 × 5 × 4.

7 × 6 × 5 × 4 = 42 × 5 × 4

= 210 × 4

= 840

EXAMPLE 2

Find the value of _ 3 6 ××^5  2 ××^4 1.

2 2

_ 3 6 ××^5  2 ×× 1 4 = _ 3 6 ××^5  2 ××^4 1

1 1

= _^201

= 20

Write each fraction in simplest form.

14. 128 15. 183


15. ^4
    16
    17. ^5
    15


16. SLEEP Use the table shown. What
    fraction of the day, in simplest form,
    does a guinea pig spend sleeping?

Average Sleep Time Per Day

Animal Number of Hours

Baboon 10

Guinea Pig 9

Gray Seal 6

EXAMPLE 3

Write _^2128 in simplest form.

÷ 7

2821 = ^34

÷ 7

Are You ReadyAre You Ready

for the Chapter?for the Chapter?

Multiply from left

to right.

Simplify. Divide out

common factors.

Multiply the numerator.

Multiply the denominator.

Divide the numerator and

denominator by the GCF, 7.

Online Option Take the Online Readiness Quiz.

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