The number of girls in a class are 7 times the number of boys, which value can never be the of total students

Answer: Option B

Explanation:

As per BODMAS rule first we will solve the terms in the bracket then other.
= 7500 + (25) = 7525

Answer: Option D

Explanation:

Let the boys are X, then girls are 7X, total = X+7X = 8X

So it should be multiple of 8, 30 is not a multiple of 8.

Answer: Option C

Explanation:

Let the number of buffaloes be x and the number of ducks be y
=> 4x + 2y = 2 (x + y) + 24

=> 2x = 24 => x = 12

Answer: Option B

Explanation:

\begin{aligned}
= 16-[5-(6+2(7-8+5))]
\end{aligned}
(Please check due to overline, sign has been changed)
\begin{aligned}
= 16-[5-(6+2 \times 4))]
\end{aligned}
\begin{aligned}
= 16-[-9] = 16 + 9 = 25
\end{aligned}

Answer: Option C

Explanation:

\begin{aligned}
= \frac{1}{2+\frac{1}{2+\frac{1}{\frac{3}{2}}}}
\end{aligned}
\begin{aligned}
= \frac{1}{2+\frac{1}{2+\frac{2}{3}}}
\end{aligned}

\begin{aligned}
= \frac{1}{2+\frac{1}{\frac{8}{3}}}
\end{aligned}

\begin{aligned}
= \frac{1}{2+\frac{3}{8}}
\end{aligned}

\begin{aligned}
= \frac{1}{\frac{19}{8}}
\end{aligned}

\begin{aligned}
= \frac{8}{19}
\end{aligned}