least number of stamps

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least number of stamps

by vivekjaiswal » Fri Sep 25, 2009 1:47 am
Kim bought a total of $2.65 worth of postage stamps in four denominations. If she bought an equal number of 5-cent and 25-cent stamps and twice as many 10-cent stamps as 5-cent stamps, what is the least number of 1-cent stamps she could have bought ?
(A) 5
(B) 10
(C) 15
(D) 20
(E) 25


OA is C
Can somebody help
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Re: least number of stamps

by mohitsharda » Fri Sep 25, 2009 2:52 am
vivekjaiswal wrote:Kim bought a total of $2.65 worth of postage stamps in four denominations. If she bought an equal number of 5-cent and 25-cent stamps and twice as many 10-cent stamps as 5-cent stamps, what is the least number of 1-cent stamps she could have bought ?
(A) 5
(B) 10
(C) 15
(D) 20
(E) 25


OA is C
Can somebody help
4 denominations are 1 cent, 5 cent, 10 cent and 25 cent.

Let there be y 1 cent stamps
and x 5 cent stamps.
25 cent stamps = x
10 cent stamps = 2x

Total value of stamps = (y*1)+(5*x)+(10*2x)+(25*x)
= y + 50x = 265 (given)
=> minimum y will be 15, for x =5.

Hence (C)
MS