Question

the monthly pocket money of Ravi and Sanjeev are in the ratio 5 : 7. their expenditures are in the ratio 3 : 5. if it saves rupees 80 each month, find their monthly pocket money...

this problem is given from ratio and proportion chapter.... so please answer this question in in ratio form...​

Answer 1

EXPLANATION.

To find their monthly pocket money.

According to the question,

Let the monthly pocket money of ravi and

sanjeev be = 5x and 7x

Let their expenditures be = 3y and 5y

Now,

=> 5x - 3y = 80 ........(1)

=> 7x - 5y = 80 ........(2)

From equation (1) and (2) we get,

=> multiply equation (1) by 7

=> multiply equation (2) by 5

we get,

=> 35x - 21y = 560

=> 35x - 25y = 400

we get,

=> 4y = 160

=> y = 40

put the value of y = 40 in equation (1)

we get,

=> 5x - 3(40) = 80

=> 5x - 120 = 80

=> 5x = 200

=> x = 40

Therefore,

monthly pocket money of ravi

=> 5 X 40 = ₹ 200

Answer 2

Answer:

Let Pocket Money be 5x and 7x & their Expenses be 3x and 5x respectively.

we have ; In both cases

⠀Ravi⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀Sanjeev

5x - 3x = 80⠀⠀⠀⠀⠀7x - 5x = 80

2x = 80⠀⠀⠀⠀⠀⠀⠀⠀2x = 80

x = 40⠀⠀⠀⠀⠀⠀⠀⠀⠀x = 40

Ravi = 5x = 5(40) = Rs. 200

Sanjeev = 7x = 7(40) = Rs. 280