3034 - (1002 / 20.04) = ?

Answer: Option C

Explanation:

= 2(3)-3(5)+(3*5) + 2(5)-3(3)+(5*3)
= 6-15+15+10-9+15 = 31-9 = 22

Answer: Option B

Explanation:

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

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 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 D

Explanation:

b-[b-(a+b)-{b-(b-a+b)}+2a]
=b-[b-a-b-{b-(2b-a)}+2a]
=b-[-a-{b-2b+a}+2a]
=b-[-a-{-b+a}+2a]
=b-[-a+b-a+2a]
=b-[-2a+b+2a]
=b-b
=0