Question

Monthly incomes of two persons are in the ratio 4 : 5 and their monthly expenses are in

the ratio 7 : 9. If each saves ` 50 per month find their monthly incomes.​

Answer 1

Answer:

400, 500

Step-by-step explanation:

Put in equation

4x+7y=50 & 5x+9y=50

then 1st equation multiple 5 and 2nd is 4

y=50 then put in 1st equation

4x=400÷4=100

income ratio is 4 ×100 =400 and 100 ×5=500

so answer is 400&500

Hope it helps you

Be happy

Answer 2

☯ Let the monthly income of one person be 4x and that of the other be 5x.

☯ Let the monthly expenses of one person be 7y and that of other be 9y.

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$\underline{\bigstar\:\boldsymbol{According \;to \;the\: given \;Question\; :}}$

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• $\sf{9x\:-\:7y\:=\:50\:\:\:\:\:\:{\red{[equation\:1]}}}$

• $\sf{5x\:-\:9y\:=\:50\:\:\:\:\:\:{\red{[equation\:2]}}}$

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On solving both equations, we get :

• ${\textsf{\textbf{y\:=\:50}}}$
• ${\textsf{\textbf{x\:=\:100}}}$

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Therefore,

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• Monthly Income of One Person :

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$\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{4\:\times\:100}$

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$\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{400 }$

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• Monthly Income of the Other Person :

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$\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{5\:\times\:100}$

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$\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{500}$

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• So, the sum of their monthly incomes :

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$\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{400\:+\:500}$

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$\:\:\:\:\:\:\::\:\Longrightarrow\:{\underline{\boxed{\frak{\pink{900}}}}}\:\bigstar$

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$\:\therefore\:{\underline{\sf{Hence,\:the \:sum \:of \:their \:monthly \:incomes\:is \:{\textsf{\textbf{Rs.\:900 }}}}}}.$

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