So finally I started studying for my GMAT which I will take in summer.
I began with Manhattan GMAT
2007 (Number properties) as it was suggested on the forum. My first question is about exponents.
On page 51, the MGMAT says the following:
5^1 = 5
5^2 = 25 Increased by 20
5^3 = 125 Increased by 100
5^4 = 625 Increased by 500
Now, my primary language is not English but why is 5^4 (aka 625) increased by 500?Why can't we say that it increased by 620? I mean that why can't we start counting from the 5^1?
Also, in Russian there are two ways how to say the number has increased:
In the example of 5^4 compared to 5^1, we can say that
a. 5^1 has increased by 620 arithmetically (that is 620 has been added)
b. 5^1 has increased by 125 geometrically (that is 5 has been multiplied by 125)
However, English language does not specify when somebody says that "Number A has increased by B". Naturally, I start thinking that a geometrical progression is being used. Nevertheless, I found out that by default the expression "Number A has increased by B" means the addition of the B.So, what are the common ways for GMAT to ask questions when multiplication (and not addition) is involved?
If the post is helpful, kudos appreciated!