SOLUTION: Could you help solve this word problem: There were 174 words typed in 3 minutes. There were 348 words typed in 6 minutes. How many words will be typed in 8 minutes?

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Question 786921: Could you help solve this word problem: There were 174 words typed in 3 minutes. There were 348 words typed in 6 minutes. How many words will be typed in 8 minutes?
Found 2 solutions by xinxin, Edwin McCravy:
Answer by xinxin(76) About Me  (Show Source):
You can put this solution on YOUR website!
the typing speed = 174/3 = 348/6 = 58 words/minutes
In 8 minutes, there will be 58*8 = 464 words typed.

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
That tutor did it an easier way. He was able to because the numbers
were easy.  But if they hadn't been, this is how you would do it:


Let x = the number of minutes
Let y = the number of words typed.

Then,
when x = 3, y = 174, and
when x = 6, y = 348

So we find the equation of the line through the two points
(3,174) and (6,348)

First we use the slope formula:

Slope formula:
m = %28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29
where (x1,y1) = (3,174)
and where (x2,y2) = (6,348)

Then the point-slope formula:

Point-slope formula:
y - y1 = m(x - x1)
where (x1,y1) = (3,174)
and where the slope m is the value you got from 
the slope formula

Then when you get the equation, solve for y,

Finally, substitute 8 minutes for x, and simplify and that
will be the answer.

Edwin