Lst question: x = 5, y = 7
2nd question: x = -1, y = 5
3rd question: x = 98, y = 80
Answer:
Paul will have no more than $ 450 in next 8 weeks.
Step-by-step explanation:
From the information given on statement, we know that Paul saves all of his earnings weekly. Then, the money save is equal to the sum of initial amount (
), measured in monetary units, and week earning (
), measured in monetary units, multiplied by a number of weeks (
), dimensionless:
(1)
Now we clear the number of weeks within the formula:
If we know that 
, 
and 
, then the number of weeks is:
Paul will have no more than $ 450 in next 8 weeks.
Answer:
60
Step-by-step explanation:
5 times 12
With amounts measured in gallons, let
x = amount of 65% antifreeze
y = amount of 90% antifreeze
1 gal of the 65% brand contains 0.65 gal of pure antifreeze; x gal would contain 0.65x gal. Similarly, y gal of the 90% brand contains 0.90y gal of pure antifreeze.
To obtain 120 gal of 80% antifreeze solution (which contains 0.80•120 = 96 gal of pure antifreeze), we must have
x + y = 120 … … … … … [total volume of antifreeze solution]
0.65x + 0.90y = 96 … [total volume of pure antifreeze]
Solve the first equation for y :
y = 120 - x
Substitute this into the second equation and solve for x :
0.65x + 0.90 (120 - x) = 96
0.65x + 108 - 0.90x = 96
0.25x = 12
x = 48
Solve for y :
y = 120 - 48
y = 72
