Question

A marble bust is 25 years old and a terra-cotta bust is 85 years old. In how many years will the terra-cotta bust be three times as old as the marble bust?​

Answer 1

In 5 years the terra-cotta bust will be thrice as old as the marble bust

Step-by-step explanation:

Difference of age between terra-cotta bust and marble bust = 85 - 25 = 60 years

Assuming marble bust as 'x' years old, we get terra-cotta bust as 'x + 60' years old

According to Question

(x + 60) + y = 3(x + y) (Where y is the number of years after which terra-cotta bust will be thrice as old as the marble bust)

(25 + 60) + y = 3(25 + y)

85 + y = 75 + 3y

85 - 75 = 3y - y

10 = 2y

y = 10/2

y = 5

So, it will take 5 years for terra-cotta bust to be thrice as old as the marble bust.