Question 200550This question is from textbook Beginning Algebra
: Hello,
I really need help with the following word problem: The engineering club ran a coffee and donut sale to raise money for the club's activities. The first week, they made a profit of $200. The second week, they sold 3 times as many donuts, but 1/2 the number of coffees, and made a profit of $225. If the profit for each donut was $.50 and the profit for each coffee was $.75, how many donuts and coffees did they sell the first week?
I would greatly appreciate any help.
This question is from textbook Beginning Algebra
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! The first week, they made a profit of $200. The second week, they sold 3 times
as many donuts, but 1/2 the number of coffees, and made a profit of $225.
If the profit for each donut was $.50 and the profit for each coffee was $.75,
how many donuts and coffees did they sell the first week?
:
let d = no. of donuts sold the 1st week
let c = no. of coffees sold the 1st week
:
First week equation:
.50d + .75c = 200
:
2nd week equation:
.50(3d) + .75(.5c) = 225
1.50d + .375c = 225
:
Multiply the above equation by 2, subtract the first equation
3d + .75c = 450
.5d +.75c = 200
-----------------Subtraction eliminate c, find d
2.5d = 250
d = 
d = 100 donuts, the 1st week
:
Find c using the 1st equation
.50(100) + .75c = 200
50 + .75c = 200
.75c = 200 - 50
.75c = 150
c = 
c = 200 coffees the 1st week
:
:
Check solutions in the 2nd week equation
1.50d + .375c = 225
1.50(100) + .375(200) =
150 + 75 = 225
|
|
|
