Question

A mixture contains $20\%$ sugar and $5\%$ salt, and the rest is flour. If the quantity of sugar in the mixture is 4 lb, find the amount of flour.

• A. 20 lb
• B. 15 lb
• C. 25 lb
• D. 30 lb

Answer 1

The correct option is B 15 lb

Percentage of sugar and salt $=20+5=25\%$
Percentage of flour $=100-25=75\%$
Now, given that 20% of the mixture is 4 lb.
So, $20\%$ of (Total amount) = 4
$\Rightarrow \frac{20}{100}\times$ (Total amount) = 4
$\Rightarrow$ Total amount $=\frac{100}{20}\times 4=20lb$

Amount of flour = $75\%$ of (Total amount) = $\frac{75}{100}\times 20=15lb$