Question

A trader buys x articles for a total cost of Rs. 600.

1. Write down the cost of one article in terms of x. If the cost per article were Rs. 5 more, the number of articles that can be bought for Rs. 600 would be four less.
2. Write down the equation in x for the above situation and solve it for x.

Answer 1

Number of articles = x

Total cost of articles = Rs. 600

i. Cost of one article = Rs. `600/x`

ii. From the given information, we have

`600/(x - 4) - 600/x = 5`

`(600x - 600 x + 2400)/(x(x - 4))  = 5`

`480/(x(x - 4)) = 1`

x² – 4x – 480 = 0

x² – 24x + 20x – 480 = 0

x(x – 24) + 20(x – 24) = 0

(x – 24)(x + 20) = 0

x = 24, –20

Since, number of article cannot be negative.

So, x = 24.