Question

The ratio of two numbers is 3:5 and the difference of the cube is 784.Find sum of numbers

Answer 1

let the two nos be 3x and 5x
a q
(5x )^3-(3x)^3=784
125x cu.-27x cu. =784
98x^3=784
×^3=8
x=2

the nos are
3x=6
5x=10
sum=3x+5x=6+10=16

Answer 2

Answer:

The sum of the is 16.

Step-by-step explanation:

Given,

The ratio of two numbers is 3:5,

Let, the first number = 3x and second number = 5x,

Where, x is any number,

The difference of the cube is,

(5x)³ - (3x)³ = 125x³ - 27x³ = 98x³

According to the question,

98x³ = 784 ⇒ x³ = 8 ⇒ x = 2,

Hence, the sum of the number = 3x + 5x = 8x = 8 × 2 = 16.