Re: If m pencils cost the same as n pens, and each pencil costs
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10 Apr 2020, 16:01
We can let p = the cost of a pen, in cents and we can create the equation:
20m = pn
20m/n = p
So the cost of each pen, in dollars, is (20m/n)/100 = 20m/100n = m/5n.
So 10 pens cost:
10 x m/5n = 2m/n dollars.
Alternate Solution:
We are told that m pencils cost the same as n pens, and pencils cost 20 cents (0.20 dollars) each, so we have:
0.20m = n
We see that n pens cost 0.20m, so the cost of one pen can be obtained by dividing by n, so we get:
0.20m/n = n/n
0.20m/n = 1
Since 1 pen costs 0.20m/n dollars, then 10 pens costs (0.20m/n) x 10 = 2m/n dollars.
Answer: C