SOLUTION: three-fourths of the students in Math 200 got a C on the last test, and one-fifth received an A. Suppose 22 more students received C's than received A's. How many students are in

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Question 1114164: three-fourths of the students in Math 200 got a C on the last test, and one-fifth received an A. Suppose 22 more students received C's than received A's. How many students are in the class?
Found 4 solutions by josgarithmetic, stanbon, ikleyn, MathTherapy:
Answer by josgarithmetic(39617) About Me  (Show Source):
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x, size of class
(3/4)x : (1/5)x is ratio of C to A.

C : A is 15 : 4.

C%2FA=15%2F4.

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Suppose 22 more students received C's than received A's.
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C-A=22
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15A=4C
15A=4%28A%2B22%29
15A=4A%2B88
11A=88
highlight%28A=8%29-------Eight students earned A.


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and one-fifth received an A.
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%281%2F5%29x=8
highlight%28x=40%29-----------class of 40 student size

Answer by stanbon(75887) About Me  (Show Source):
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three-fourths of the students in Math 200 got a C on the last test, and one-fifth received an A. Suppose 22 more students received C's than received A's. How many students are in the class?
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Equations:
(2/3)s = (1/5)s +22
----
((10-3)/15))s = 22
(7/15)s = 22
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s = 47.14
Note:: The answer must be a whole number. Please check your post.
Cheers,
Stan H.
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Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.
Let x = all the population of the class.


%283%2F4%29%2Ax = 0.75x  got a C.


%281%2F5%29%2Ax = 0.2x  got an A.


The difference  is  0.75x - 0.2x = 0.55x,  or 22.


The equation is  0.55x = 22.


The answer is  22%2F0.55 = 40.

Solved.


Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

three-fourths of the students in Math 200 got a C on the last test, and one-fifth received an A. Suppose 22 more students received C's than received A's. How many students are in the class?
There's NOTHING wrong with your post. It's perfectly fine, so IGNORE the person who says there is!!

Let number of students in class be S

Then number that received a C = matrix%281%2C3%2C+%283%2F4%29S%2C+or%2C+3S%2F4%29 and number that received an A = matrix%281%2C3%2C+%281%2F5%29S%2C+or%2C+S%2F5%29

We then get: matrix%281%2C3%2C+3S%2F4%2C+%22=%22%2C+S%2F5+%2B+22%29

15S = 4S + 440 ------- Multiplying by LCD, 20

15S – 4S = 440

11S = 440

S, or number of students in class = highlight_green%28matrix%281%2C3%2C+440%2F11%2C+%22=%22%2C+40%29%29