Equations
List the inverse for * addition * subtraction * multiplication * division
* addition - subtraction * subtraction - addition * multiplication - division * division - multiplication
Mary sells 30 boxes of cookies in 5 hours. What is her unit rate in boxes per hour?
6 boxes per hour
a+2c = g, c = ?
c = (g-a)/2
14 less than twice a number is 30
2x - 14 = 30, x = 22
3n − 5 = −8(6 + 5n)
n=-1
x - 3 = 11 what is the first step for this problem?
Add 3 to both sides
The ratio of dogs to cats at an animal shelter is 3:1. If there are 45 dogs, how many cats are there?
15 cats
3x+2y = 1, y = ?
y = (1-3x)/2
If 2 more than twice a number is 16, find the number
2+2x=16, x = 7
2(4x − 3) − 8 = 4 + 2x
x=3
2x+3x+4=6
x = 2/5
Solve for x:
x/5 = 7/10
x=3.5
I=Prt , r = ?
r = (I/Pt)
Together, a burger and fries cost $12. Find the price of each if the burger costs 3 times as much as the fries
b+f = 12 , b = 3f, f = 3, b=9
24a − 22 = −4(1 − 6a)
no solution
27x - 3(x-6) = 6
x = -0.5 or x = -(1/2)
Solve for y:
4/(1-y)=8/20
t = ghr , r = ?
(t/gh)
Joe at 4 cookies. Mary at 7 cookies. The total price for all the cookies was $33. What is the cost of each cookie?
4c + 7c = 33, 11c = 33, c = 3
−3(4x + 3) + 4(6x + 1) = 43
x=4
7x+15 = 71, 7 - y = 9, what is the product of x and y?
x = 8, y = -2, product = -16
32 is what percent of 80?
40%
y = 1/4xz, z = ?
4y/x
Laura spent a total of $66 for manicure and pedicure. Pedicure cost twice as much as manicure. What is the cost of manicure? What is the cost of pedicure?
m+p = 66, p = 2m, m = 22, p = 44
−5(1 − 5x) + 5(−8x − 2) = −4x − 8x