Question 3

Two whole numbers are such that the cube of first number exceeds the cube of second by 61 and the ratio of the numbers is 5:4. What is the value of larger number?

Solution

Let the numbers be $$5x$$ and $$4x$$

According to ques,

=> $$(5x)^3-(4x)^3=61$$

=> $$125x^3-64x^3=61x^3=61$$

=> $$x^3=\frac{61}{61}=1$$

=> $$x=\sqrt[3]{1}=1$$

$$\therefore$$ Larger number = $$5\times1=5$$

=> Ans - (C)

Share on Whatsapp Share on Whatsapp

Create a FREE account and get: