M7MBA wrote:What is the ratio of 2a to b?
(1) a/b = 2
(2) a + b = 5
The OA is A.
How can I find the ratio without knowing the value of a and b? And why is not sufficient the second statement?
Hello M7MBA.
Let's take a look at your question.
We need to find the quotient $$\frac{2a}{b}=?$$
First statement
(1) a/b = 2
Here, we can multiply by 2 and we get $$2\cdot\frac{a}{b}=2\cdot2\ \ \ \Rightarrow\ \ \ \frac{2a}{b}=4.$$ So, this statement
is sufficient.
Second statement
(2) a + b = 5
Here, if we suppose that "a" and "b" are integers then we could get different cases:
- a=1, b=4 and then $$\frac{2a}{b}=\frac{2\cdot1}{4}=\frac{2}{4}=\frac{1}{2}.$$
- a=4, b=1 and then $$\frac{2a}{b}=\frac{2\cdot4}{1}=\frac{8}{1}=8.$$ Since we get different answers, we conclude that this statement
is not sufficient.
Therefore, the correct answer is the option
A.
I hope it helps you. <i class="em em-smiley"></i>
