Chapter 8 linear appliCaTionS 269
- 65% 25% 40%
ml
+ 180 – x^
ml
=^180
ml
0.65x + 0.25(180 – x) = 0.40(180)
0650 25 180 04 0 180
06545025 72
04
..().( )
..
.
xx
xx
+−=
+− =
004572
45 45
04027
27
040
675
x
x
x
x
+=
−−
=
=
=
.
.
.
Add 67.5 ml of 65% acid solution to 180 – x = 180 – 67.5 = 112.5 ml of
25% solution to produce 180 ml of 40% acid solution.
- 0% 45% 30%
liters
+^10
liters
= x + 10^
liters
0 x + 0.45(10) = 0.30(x + 10)
00 45 10 03010
045030 3
30 3
15 0
xx
x
+=+
+= +
−−
=
.().()
..
.
.. 330
15
030
5
x
x
x
.
.
=
=
Add 5 liters of water to 10 liters of 45% alcohol solution to produce a
30% alcohol solution.