SOLUTION: Pencils cost 25 cents a piece. Pens cost 80 cents a piece. Susan spent 20 dollars for a total of 36 pens and pencils. How many pencils did she buy? And: The ratio of two num

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Question 15875: Pencils cost 25 cents a piece. Pens cost 80 cents a piece. Susan spent 20 dollars for a total of 36 pens and pencils. How many pencils did she buy?

And:
The ratio of two numbers is 8 to 5. the difference of the numbers is 24. what are the numbers?

Answer by sbasics2005(1) About Me  (Show Source):
You can put this solution on YOUR website!
Let Number of pencils bought be 'x' and pens be 'y'.
Then 25x + 80y = 2000 ----- (1) and x + y = 36 ------- (2)
5x + 16y = 400 [Divide eq (1) with 5.]
5x + 5y = 180 [Multiply eq (2) with 5.]
11y = 220
y = 20
x + 20 = 36 [Use eq(1).]
x = 16
Therefore, Susan bought the number of pencils are 16.
And
Let the two numbers be 8x and 5x.
8x - 5x = 24
3x = 24
x = 8
Therefore, the numbers are 64 and 40.