Along a yard 225 metres long, 26 trees are palnted at equal distances, one tree being at each end of the yard. What is the distance between two consecutive trees

Answer: Option D

Explanation:

We know
\begin{aligned} 2ab = (a^2 + b^2) - (a - b)^2 \end{aligned}

\begin{aligned} 2pq = 29 - 9 = 20 \end{aligned}

\begin{aligned} =>pq = 10 \end{aligned}

Answer: Option A

Explanation:

\begin{aligned}
=> \frac{4}{7}x + \frac{4}{7} = \frac{15}{4}
\end{aligned}
\begin{aligned}
= \frac{4}{7}x = \frac{15}{4} - \frac{4}{7}
\end{aligned}
\begin{aligned}
= \frac{4}{7}x = \frac{7}{14}
\end{aligned}
\begin{aligned}
= x = \frac{1}{2}\times \frac{7}{4} = \frac{7}{8}
\end{aligned}

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 A

Explanation:

Tip:
As you can see, there is bar over
\begin{aligned}
\overline{\frac{1}{4}-\frac{1}{6}}
\end{aligned}
So their sign will be changed from - to + as
\begin{aligned}
\frac{1}{4}+\frac{1}{6}
\end{aligned}