Question

A mixture consists of $45\frac{5}{11}\%$ sand, $36\frac{4}{11}\%$ gravel and rest cement .Find the weight of mixture which contains $12.5kg$ wt of sand . Also determine the weight of mixture that will contain $4kg$ wt of cement .

Answer 1

Let the mixture be $100$

Quantity of sand in the mixture = $\frac{500}{11}$%

Quantity of gravel in the mixture = $\frac{400}{11}$%

Quantity of Cement in the mixture $=100$ $\frac{500}{11}\%-\frac{400}{11}\%$

$\Rightarrow \frac{1100÷500-400}{11}\%$

$\Rightarrow \frac{200}{11}\%$

Let $xKg$ of mixture contain $12.5Kg$ of sand

But $100$ of mixture contains $\frac{500}{11}\%$ of sand

$\Rightarrow \frac{x}{100\%}=\frac{12.5}{\frac{500}{11}\%}$

$\Rightarrow x=\frac{12.5\times 100\%}{500\%}\times 11Kg$

$=2.5\times 11kg$

$=27.5Kg$

let $yKg$ of mixture contain $4Kg$ of cement

But $100$ of mixture contain $\frac{200}{11}\%$ discount

$\Rightarrow \frac{y}{100\%}=\frac{4}{\frac{200}{11}\%}$

$y=22Kg$