Question

the length are in the ratio 3:7. the second length is 42m find the 1st length

Answer 1

Answer:

18 m

Step-by-step explanation:

Let the ratio be 3x : 7x.

According to Question,

7x = 42

=> x = 42/7

=> x = 6

Hence, first length = 3×6 m = 18 m

Answer 2

Answer :-

• The 1st length = 18 m.

Given :-

• Two lengths are in the ratio 3 : 7.
• The second length is 42 m.

To find :-

• The 1st length.

Step-by-step explanation :-

The two lengths are in the ratio 3 : 7.

Therefore, let the two lengths be 3x and 7x.

First length = 3x.

Second length = 7x.

The second length = 42 m.

Thus, we get :-

$\sf \bf 7x = 42 \:m$

$\sf \bf x = \dfrac{42}{7}$

$\sf \bf x = 6 \:m.$

Since x = 6 m,

Therefore,

The first length = 3x = 3 × 6 m = 18 m.

The second length = 7x = 7 × 6 = 42 m.

Verification :-

To check your answer, just find the ratio of the first and second length in simplest form and see if it is 3 : 7.

So, lets do it!

$\sf \bf \dfrac{18}{42} = \dfrac{6}{14} = \dfrac{3}{7} = 3 : 7.$

Since the ratio of the first and the second length in simplest form is 3 : 7,

Hence verified!