Question
Find the value of the unknown in the following proportion :
c
c
✓
Answer
$a : \frac{9}{2}:: \frac{7}{2}: \frac{11}{2}$
$\Rightarrow a \times \frac{11}{2}=\frac{9}{2} \times \frac{7}{2}$
$\Rightarrow a =\frac{9}{2} \times \frac{7}{2} \times \frac{2}{11}$
$\Rightarrow a =\frac{63}{22} $
$a =\frac{63}{22}$
$\Rightarrow a \times \frac{11}{2}=\frac{9}{2} \times \frac{7}{2}$
$\Rightarrow a =\frac{9}{2} \times \frac{7}{2} \times \frac{2}{11}$
$\Rightarrow a =\frac{63}{22} $
$a =\frac{63}{22}$
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