Question

Two number are in the ratio 4:7 and their lcm is given as 840. find the greatest among the two numbers.

Answer 1

two no are in the ratio 4:7
seprate no. by taking x with them

4x. 7x

lcm=840 4 ×7/850

30
7×30=210
4×30=120

Answer 2

Answer:

The greatest number is 210.

Step-by-step explanation:

Given : Two number are in the ratio 4:7 and their LCM is given as 840.

To find : The greatest among the two numbers.

Solution :

LCM  is least common multiple or a number that can be fairly divided by each of the numbers taken initially.

Let us suppose the common multiple to be x i.e, HCF = x

and ratio became 4x and 7x

We know,

$\text{Product of two numbers}=\text{LCM}\times \text{HCF}$

According to question,

$4x\times 7x=840\times x$

$28x^2=840x$

$x=\frac{840}{28}$

$x=30$

Therefore, The numbers are

4x=4(30)=120

7x=7(30)=210

So, The greatest number among them is 210.