Question

A runs 7 / 4 times as fast as



b. if a gives b a start of 90 m, how far must the winning post be so that a and b might reach it at the same time?

Answer 1

If A runs 7/4 times as fast as B

⇒ A : B = 7 : 4

Define x:

Let x be the constant ratio

A : B = 7x : 4x

Solve x:

The difference is 90m

7x - 4x = 90

3x = 90

x = 30m

Find the distance of the winning post:

The winning post is the distance A has to run

A = 7x = 7(30) = 210 m

Answer: The winning post has to be 210 m away.

Answer 2

$<b>$Answer :

A = 7

B = 4

Ratio :

A : B = 7 : 4

Let the common ratio = x

A = 7x

B = 4x

A gives B a start of 90m i.e.

Difference between them.

Hence, your equation becomes :

$= > 7x - 4x = 90 \\ \\ = > 3x = 90 \\ \\ = > x = \frac{90}{3} \\ \\ = > x = 30$

The winning post :

=> A = 7x

=> A = 7 × 30

=> A = 210

$\color{blue}\underline\textbf{Hence, 210m is your required answer. }$

Tysm for the question!