Question Detail

a * b = 2a - 3b + ab, then 35 + 53 = ?

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

1. Simplify
\begin{aligned} 1+\frac{1}{2}+\frac{1}{4}+\frac{1}{7}+\frac{1}{14}+\frac{1}{28} = ? \end{aligned}

Answer: Option A

Explanation:

By taking LCM we get
=\begin{aligned} \frac{28+14+7+4+2+1}{28}
= \frac{56}{28} = 2\end{aligned}

2. 3640 ÷ 14*16 + 340 = ?

3500
4500
1500
2500

Answer: Option B

3. \begin{aligned}
(3\frac{1}{4}\div \{1\frac{1}{4} - \frac{1}{2}(2\frac{1}{2} - \overline {\frac{1}{4} - \frac{1}{6}} ) \} )
\end{aligned}

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}

4. \begin{aligned}
\frac{4+4 \times 18 -6 - 8}{123 \times 6 - 146 \times 5 }
\end{aligned}

7.50
7.75
8
8.05

Answer: Option B

Explanation:

\begin{aligned}
\frac{4+72-6-8}{738-730}
\end{aligned}
\begin{aligned}
= \frac{76-14}{8}
\end{aligned}
\begin{aligned}
= \frac{62}{8} = 7.75
\end{aligned}