6th Grade Math Textbook, Progress

Evaluate Multiplication and

Division Expressions

3-11

Evaluate each expression.

1. 26 • 2010 2. 0.25
   8
   30.4 3. 4.2n, for n 20


2. 33 t, for t1.3 5. 0.5r, for r 6000 6. 345 f, for f 15


3. 
   
   
   
   8. , for q1.2 9. , for x2.94
   
   
   
   


4. n160, for n 2992 11. 2 • y•6, for y0.1 12.a(2.1 •0.02), for a 40

x

0.07

8.4

q

7568

16

A train travels at an average rate of 130

miles per hour. After a number of hours,

the train reaches its destination. How many

miles does the train travel in 2.5 hours?

To find how many miles, write the

expression:

130 h

Evaluatemeans find the value.

value of the expression

130 h 130 • 2.5

 325

Let hrepresent the number

of hours traveled.

Then evaluate 130h, whenh2.5 hours.

To evaluate an algebraic expression:

• Substitute the given number
  for the variable.


• Simplify to find the value
  of the expression.

The train travels 325 miles in 2.5 hours at 130 miles per hour.

Study these examples.

Evaluate each expression for the value given.

w20, when w$500 8 a
n, when a1.5 and n 4

w  20 Replacewwith $500. 8 a
n Replaceawith 1.5 andnwith 4.

$500 20 Divide. 8 
1.5
 4 Multiply.

$25 48

1.1

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