6th Grade Math Textbook, Progress

Evaluate Algebraic Expressions

4-3

Evaluate each expression.

1. 56
   p(qr), when p3, q4.2,
   and r5.1


2. 15 cj^3 , when c6 and j 5

Some students are visiting a science

museum. They pay $7 per student and

a group fee of $25. Write an algebraic

expression for the total cost of the trip.

Let srepresent the number of students.

total students’ group

cost plus fee

$7s  $25

If there are 124 students going on the trip,

what is the total cost they will pay for the trip?

To find the total cost, evaluate the

expression $7s$25, when s124.

$7s$25

$7• 124 $25 Replace swith 124.

$868 $25 Simplify using the order of operations.

$893

The students will pay a total cost of $893.

Study these examples. Evaluate each expression for the values given.

7  3 x^3 
y, when x 2

and y 4

7  3 • 23 
 4 Replace xwith 2 and ywith 4.

7  3 • 8 
 4 Simplify using the order

7  24 
 4 of operations.

31 
 4

27

, when a4, b0.3,

and c0.2

280

28

0.1

12  42

0.3
0.2

12 a^2

b
c

Replace awith 4, bwith 0.3,

and cwith 0.2.

Simplify using the order

of operations.

2. (x1)^2 yz, when x3,
   y8.8, and z 4


3. (de9)^2
   14 f, when d8,
   e45, and f 2

Remember:

To evaluate an expression

is to find its value.

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