SOLUTION: The number of pages read varies directly as the number of minutes. If you can read 20 pages in 45 minutes, how many pages can you read in 18 minutes?

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Question 1122141: The number of pages read varies directly as the number of minutes. If you can read 20 pages in 45 minutes, how many pages can you read in 18 minutes?
Found 2 solutions by josmiceli, ikleyn:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +y+ = number of pages read
Let +x+ = minutes to read +y+ pages
————————-
For direct proportion I can say:
+y+=+k%2Ax+ where +k+ is a constant
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If +y+=+20+, then +x+=+45+
+20+=+k%2A45+
+k+=+4%2F9+
———————
If +x+=+18+ then:
+y+=+k%2A18+
+y+=+%284%2F9%29%2A18+
+y+=+8+
——————-
You can read 8 pages in 18 min

Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
If you read 20 pages in 45 minutes at the constant rate,


then you read 4 pages in 9 minutes


and 8 pages in 18 minutes.