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a) $\frac{1}{4}$: $\frac{1}{2}$: $\frac{1}{5}$ = 5: 10: 4
$\frac{1}{4}$ = $\frac{5}{19}$ x 1000
= 263. 16 cm3
$\frac{1}{5}$ = $\frac{4}{19}$ x 1 000
210.53 cm3
b) Let volume of 45% concentration be x 25% will be (100 - x)
0.45x + 0.25 (100 - x) = 30%
0.45x + 25 - 0.25x = 30
0.2x = 5; 2x = 50
x = 25 cm3
Hence volume of 45% = 25 cm3
Volume of 25%
= 75%
Ratio 25:75 = 1:3
c) 1 Kg of mixture cost
$\frac{140 + 2 + 160\times 3}{5}$ = $\frac{760}{5}$
$\frac{280\times 480\times }{5}$ = $\frac{760}{5}$
= sh 152
% gain is $\frac{240 - 152}{152}$ x 100
= $\frac{88}{152}$ x 100 = 57.9%
johnmulu answered the question on March 2, 2017 at 12:37
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