N= night c= child
sandy= $10+$5c
kimmi= $25n
if sandy babysits 3 children for one night they will both be the same price
sandy= $10+5(3)=$25
kimmi= $25
You have to make them have their least common denominator to add or subtract, in this case 36.
Multiply 1/12 by 3, to get the denominator 36: 3/36.
Multiply 7/9 by 4, to get the denominator 36: 28/36.
Now add the numerators: 3+28=31, 31/36 is as simplified as possible so your answer is 31/36 :) I hope this helps :)
Answer:
Russell family's sprinkler: 40 hours
Gonzales family's sprinkler: 20 hours
Step-by-step explanation:
Let's call the amount of time the Russell family's sprinkler was on by X, and the Gonzales family's sprinkler by Y.
We can then formulate the equations:
X + Y = 60
X*35 + Y*40 = 2200
We can solve this system multiplying the first equation by 35, and then subtracting the result from the second equation:
35*X + 35*Y = 2100
5*Y = 100
Y = 20
from the first equation:
X + 20 = 60
X = 40
Russell family's sprinkler: 40 hours
Gonzales family's sprinkler: 20 hours
