Average of five numbers is 27. If one number is excluded the average becomes 25. The excluded number is

Answer: Option B

Explanation:

X =((3y+3z)/6)
or
2X= y + z

Answer: Option A

Answer: Option D

Explanation:

Prime numbers between 30 and 50 are:
31, 37, 41, 43, 47

Average of prime numbers between 30 to 50 will be
\begin{aligned}
(\frac{31+37+41+43+47}{5}) = \frac{199}{5} = 39.8
\end{aligned}

Answer: Option D

Explanation:

As number of girls and boys is not given so result cant be computed

Answer: Option B

Explanation:

\begin{aligned}
Average = (\frac{10+15+20+25+30}{5}) = \frac{100}{5} =20
\end{aligned}