In a group of ducks and buffaloes, the total number of legs are 24 more than twice the number of heads. Find the total number of buffaloes.

Answer: Option C

Explanation:

Remember the formula, if not then cram it :)
\begin{aligned} 2ab = (a^2 + b^2)- (a-b)^2 \end{aligned}
=> 2ab = 29 - 9 = 20
=> ab = 10

Answer: Option B

Explanation:

18800 / 470 / 20 = (18800 / 470) / 20 = 40 / 20 = 2

Answer: Option C

Explanation:

We need so simple divide 42.5/0.85,
=(4250/85) = 50

Answer: Option B

Explanation:

= (31/10) * (3/10) + (7/5) / 20
= (3.1) * (.3) + (1.4) / 20
= 0.93 + 0.07
= 1

Answer: Option D

Explanation:

\begin{aligned}
= 3034 -( \frac{1002}{2004} \times 100)
\end{aligned}
\begin{aligned}
= 3034 - 50 = 2984
\end{aligned}