The average price of three items of furniture is Rs 15915. If their prices are in the ratio 3 : 5 : 7, the price of the costliest item (in Rs) is

Correct option is B

Given: 

the average price of three items of furniture is Rs 15,915

their prices are in the ratio 3:5:7

the price of the costliest item  = ? 

Solution: 

Let the prices of the items be $3x$, $5x$, and $7x$, where $x$ is a common factor.

​The total price of the three items is the sum of the individual prices:

​$$3x+5x+7x=15x$$ 

We are given that the average price of the three items is Rs 15,915. The formula for the average price is:

​$$\frac{\text{Total price}}{3} = 15,915$$ 

​So, the total price of the three items is:

Total price = 15,915 × 3 = 47,745 

We know that the total price is also $15x$, so:

15x = 47,745

​$$x = \frac{47,745}{15} = 3,183$$ ​

The costliest item corresponds to the price 7x. Now, substitute x = 3,183:

Price of the costliest item = 7x = 7 × 3,183 = 22,281

Thus The price of the costliest item is Rs 22,281. ​