Pre-algebra chapter 7 Review

Multi-step equations

100

8a + 4a= 144

a=12

200

23 -7(x+3) +5x =10

x =-4

300

3(n-2) = 36

n=14

400

16 = 2(x-1) - x

x=18

500

8 - 3( x - 4 ) = 4 

x = 5 1/3

Multi-step decimals and fractions

100

(5/8)c - 8 = 12

c=12

200

0.7c -10 =0.5

c= 15

300

(3/4)(b+8)=15

b=12

400

-0.8k -3.1 =-8.3

k = 6.5

500

(x/4) - (3x/2) = -1/2

x=2/5

Write an equation

100

Mina buys 3 shirts for 22 dollars each and a two pairs of jeans (both pairs cost the same amount). Mina spent $100 at the store. Write the equation and solve.

x=17 dollars

200

Emma rents a bounce house for her three day birthday party. Each day costs $25 and $2 per person that jumps. If Emma spends $161 on the bounce house, how many friends did she have show up? Write the equation and solve

25(3) + 2x= 161

x=43

300

I made two batches of brownies for a party. Julia made some batches of brownies to help out. Each batch was then cut into 12 pieces and sold. There were a total of 120 pieces to sell. How many batches of brownies did Julia bring? Write the equation and solve

2(12) + x(12) = 120

24 + 12x = 120

12x= 96

x=8

400

Presley finds a jacket that she really likes for $54 after it is 25% off. What was the original price? Write the equation and solve.

1x -0.25x = 54

x=72

500

Sarah has 2 more quarters than dimes. She has $2.25 total. How many quarters and dimes does Sarah have? Set up the equation and solve. 

.1(d) + 0.25(q) = 2.25

q = d + 2

5 dimes 

7 quarters

inequalities

100

6n-3<-9

n<-1

200

3m-8>-30+5m

m<11

300

3 + (b/3) < 7

b< 12

400

-3x -3 <2x -83 

x>16

500

4 (5 - 3b) > 4 (b+1)

b < 1

isolating a variable

100

C + 273.15 = K for C

C= K - 273.15

200

pv=nrt for r

pv/nt = r

300

g=3+4a for a

a = (g-3)/4

400

 g=4x/5, for x

x = 5g/4

500

z =(10y+3x)/5 , for x

x= 5z - 10y/3