Question

Three numbers are in the ratio of 3:5:9. Find the largest number, given the sum of the squares of the
numbers is 460.
a) 10
b) 9
c) 6
d) 18​

Answer 1

Answer:

Step-by-step explanation:

Let the value of the numbers in the ratio be 3x,5x &9x.

Now,

According to the question,

(3x)^2 + (5x)^2 + (9x)^2 = 460

》9x^2 + 25x^2 + 81x^2 = 460

》115x^2 = 460

》x^2 = 460 / 115

》x^2 = 4

》x = 2

Therefore,

3x = 3×2 = 6;

5x = 5×2 = 10;

9x = 9×2 = 18;

Hence, the largest number is 18.

Answer 2

Answer:

d) 18

Step-by-step explanation:

Begin by assuming the numbers.

Since the ratio is given as 3 : 5 : 9,

Let the numbers be 3x, 5x and 9x.

According to the question we can easily derive the below written equation,

( 3x ) ^ 2 + ( 5x ) ^ 2 + ( 9x ) ^ 2 = 460

9x^2 + 25x^2 + 81x^2 = 460

115x^2 = 460

x^2 = 460 / 115

x^2 = 4

x = √4

x = 2

Hence,

The largest number = 9x = 9 * 2 = 18

Similarly, if you like you may find other numbers too