Chapter 8 linear appliCaTionS 259- Let x represent the number of quarters. There are as many dimes as
quarters, so x also represents the number of dimes. There are half as
many nickels as quarters, so^12 x (or 0.50x) is the number of nickels.
025
010.
.
x
x= amount inquarters
= amount indimees
00 .( 50 .) 50 x = amount innickels025010 005050 225
025010 00...(.).
xx x
xx++ =
++ 225 225
0 375 225
225
0 375
6x
x
x
x=
=
=
=
There are 6 quarters, 6 dimes, 0.50x = 0.50(6) = 3 nickels.- As both the number of quarters and dimes are being compared to the
number of nickels, let x represent the number of nickels. Then 2x repre-
sents the number of quarters and^12 x (or 0.50x) is the number of dimes.
005
010050
.(.)
x
x = amountofmoneyinnickels
=amountofmoneyindimes
02 .( 52 x) = amountofmmoneyinquarters0050100500252480
005005 050..(. ).().
xxx
xx++=
++xx
x
x
x=
=
=
=480
060480
480
060
8
There are 8 nickels, 0.50x = 0.50(8) = 4 dimes, and 2x = 2(8) = 16 quarters.Investment Problems
We now learn how to solve basic investment problems. An amount of money
is divided into two investments earning different interest rates. We are told how
much interest is earned in a year, information that we will use to determine
how much was invested at each rate.