The average age of A and B is 30-years, if C were to replace A, The Average would be 34-years and if C were to replace B The Average would be 33. what are the ages of A, B and c respectively:
Answers
Answer:
Let the present age of Meera be x years and Manu's age be y years respectively.
Their ages four years ago,
Meera's age = (x – 4) years
Manu's age = (y – 4) years
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\begin{gathered}\underline{\bigstar\:\boldsymbol{According\; to\; the\; Question :}}\\\end{gathered}
★AccordingtotheQuestion:
Four years ago, Meera's age was three times the age of Manu.
\begin{gathered}:\implies\sf~~~ (x - 4) = 3(y - 4) \\\\\\\end{gathered}
:⟹ (x−4)=3(y−4)
\begin{gathered}:\implies\sf ~~~x- 4 = 3y - 12 \\\\\\\end{gathered}
:⟹ x−4=3y−12
\begin{gathered}:\implies\sf ~~~x - 3y = - 8 \qquad\qquad\qquad\sf\Bigg\lgroup eq^{n} \;(i)\Bigg\rgroup\\\end{gathered}
:⟹ x−3y=−8
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Also,
After eight years Meera's age is twice the age of Manu.
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Their ages after eight years,
Meera's age = (x + 8) years
Manu's age = (y + 8) years
\begin{gathered}:\implies\sf ~~~(x + 8) = 2(y + 8) \\\\\\\end{gathered}
:⟹ (x+8)=2(y+8)
\begin{gathered}:\implies\sf ~~~x + 8 = 2y + 16\\\\\\\end{gathered}
:⟹ x+8=2y+16
\begin{gathered}:\implies\sf ~~~x - 2y = 8\qquad\qquad\qquad\sf\Bigg\lgroup eq^{n} \;(ii)\Bigg\rgroup\\\end{gathered}
:⟹ x−2y=8
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⠀⠀⠀\begin{gathered}\underline{\bf{\dag} \:\:\mathfrak{Using\;eq^{n}\;(i)\;\&\;eq^n \;(ii)\: :}}\\\\\end{gathered}
†Usingeq
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\begin{gathered}\longrightarrow\sf ~~~x - 2y - x - 3y = 8 + 8\\\\\\\end{gathered}
⟶ x−2y−x−3y=8+8
\begin{gathered}\longrightarrow\sf ~~~-2y + 3y = 16\\\\\\\end{gathered}
⟶ −2y+3y=16
\begin{gathered}\longrightarrow{\pmb{\sf ~~~ y = 16}}\\\\\end{gathered}
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y=16
y=16
⠀⠀⠀\begin{gathered}\underline{\bf{\dag} \;\:\mathfrak{Using\;eq^{n}\;(ii)\: :}}\\\\\end{gathered}
†Usingeq
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\begin{gathered}\longrightarrow\sf~~~x - 2y = 8\\\\\\\end{gathered}
⟶ x−2y=8
\begin{gathered}\longrightarrow\sf~~~ x - 2(16) = 8\\\\\\\end{gathered}
⟶ x−2(16)=8
\begin{gathered}\longrightarrow\sf\;\;\; x - 32 = 8\\\\\\\end{gathered}
⟶x−32=8
\begin{gathered}\longrightarrow\sf \;\;\;x = 8 + 32\\\\\\\end{gathered}
⟶x=8+32
\begin{gathered}\longrightarrow{\pmb{\sf\;\;\; x = 40}}\\\\\\\end{gathered}
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x=40
x=40
\therefore{\underline{\textsf{Hence, Meera's age and Manu's age is \textbf{16 years, 40 years} respectively.}}}∴
Hence, Meera’s age and Manu’s age is 16 years, 40 years respectively.