The ratio of monthly incomes of A and B is 7: 8 and their monthly expe...
Given, ratio of monthly incomes of A and B is 7: 8.
Let the monthly incomes of A and B be 7a and 8a respectively, where a is any constant
Ratio of monthly expenditures is 3: 4
Let the monthly expenditures be 3b and 4b respectively, where b is any constant
Given, each of them saves Rs. 400
∴ 7a – 3b = 8a – 4b = 400
⇒ a = b
∴ 7a – 3a = 400
⇒ a = 100
Sum of their income = 7a + 8a = 15a
⇒ Sum of their income = Rs. 1500
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The ratio of monthly incomes of A and B is 7: 8 and their monthly expe...
Given:
- The ratio of monthly incomes of A and B is 7:8.
- The ratio of their monthly expenditures is 3:4.
- Each of them saves Rs. 400 per month.
To find:
The sum of their monthly incomes.
Solution:
Let's assume the monthly income of A is 7x and the monthly income of B is 8x.
Monthly Expenditures:
The ratio of their monthly expenditures is 3:4.
So, the monthly expenditure of A is (3/7) * 7x = 3x.
And the monthly expenditure of B is (4/8) * 8x = 4x.
Savings:
Each of them saves Rs. 400 per month.
So, the savings of A is 7x - 3x - 400 = 4x - 400.
And the savings of B is 8x - 4x - 400 = 4x - 400.
Since both A and B have the same savings, we can equate their savings:
4x - 400 = 4x - 400.
Simplifying, we get 0 = 0.
This means that the equation is satisfied for any value of x. So, we can choose any value for x.
Sum of Monthly Incomes:
The sum of their monthly incomes is 7x + 8x = 15x.
Since x can be any value, we can choose x = 100 to make the calculations easier.
Substituting x = 100:
Sum of monthly incomes = 15x = 15 * 100 = 1500.
Therefore, the sum of their monthly incomes is Rs. 1500.