question_answer

If \[4a+5y=83\]and \[\frac{3a}{2b}=\frac{21}{22},\]then find the value of

A)  11                               

B)  7        

C)  4        

D)  3

Correct Answer: C

Solution :

According to question,

\[4a+5b=83\]                            ...(i)

and       \[\frac{3a}{2b}=\frac{21}{22}\Rightarrow \frac{a}{b}=\frac{7}{11}\]

By solving Eq. (i) and Eq. (ii), we get

\[b=\frac{913}{83}\]and\[a=7\]

\[\therefore \]      \[b-a=11-7=4\]