Question

The owner of a milk store finds that he can sell $980\,L$ of milk each week at ?

• A. $1240 \,L$
• B. $1340 \,L$
• C. $1350 \,L$
• D. None of these

Answer 1

Answer: (B)

$1340 \,L$

Answer 2

Let price and litre be denoted in ordered pair $(x, y)$, where $x$ denotes the ? Given $(14, 980)$ and $(16,1220)$ are two points. Then, equation of line passing through $(14, 980)$ and $(16, 1220)$ is $y-980=\frac{1220-980}{16-14}\left(x-14\right)$ $\Rightarrow y - 980 = 120x - 1680$ $\Rightarrow 120x-y=700$ Put $x=17$, we get $\left(120 \times 17\right)-y=700$ $\Rightarrow y = 2040 - 700$ $\Rightarrow y=1340$ So, he will sell weekly $1340\,L$ of milk at the rate of ?