The GRE is one of the most important tests for graduates. But due to its counter-intuitive nature, various math misconceptions during GRE preparation reduce efficiency. These GRE math misconceptions may seem true, but aren’t, which is why it is necessary to stay prepared for these myths on the GRE day.
1 is not prime.
2 is the smallest prime number.
Despite the fact that 1 can’t be divided by other integers, mathematicians have concluded 1 to be not prime. This makes many mathematical theorems simple.
**Don’t worry! These theorems won’t appear in the GRE test. Just remembering 1 is not prime is enough.
Suppose, y = USD 100 and x = USD 125. Although x is greater than y by 25%, the reverse is not true.
For instance, if x is the price of a jacket and y is the price of a sweater, then the fact that the jacket costs 25% more than the sweater is true. However, if we say that the sweater costs 25% lesser than the jacket, it means that the cost of the sweater is USD 93.75.
‘Percent less than’ and ‘percent more than’ are two non-interchangeable aspects.
This may be true in some instances but not always. Take the following expression, for example.
It can be written as:
= 1/ (- 3)4
= 1 / (-3)(-3)(-3)(-3)
= 1 / 81
Dividing both sides by x will give you x = 3 as answer. However, the correct answer should be x = 3 and x = 0. Let’s understand how:
3x2 – 1x = 8x
3x2 – 9x = 0
3(x2 – 3x) = 0
(x2 – 3x) = 0
(x – 0)(x – 3) = 0
As x is a variable, it is likely that x can be equal to 0. Dividing both LHS and RHS of the equation by x (or any present variable) should only be considered if you are sure that this variable is not equal to 0.
If you have 10 male and 40 females in the team, then there are 10 male members in a team of 50. This means 1/5th people in the team are male.
Fractions are a part of a certain whole number. In this particular case, the fraction is male and the whole number corresponds to everyone in the team, which means both males and females. Hence, the denominator of the ‘fraction of males’ in the team should be the sum of males and females and not just females.
Since ¼ is smaller than ½, it is commonly assumed that the negative forms of these fractions follow the same rule. However, the easiest method to eliminate this misconception is to draw fractions of a number line.
Using the basic rule of the number line, the fractions or numbers falling to the right are greater than the numbers to the left. Hence, -1/4 is greater than -1/2.
Representing this as an inequality:
Inclusive means including 18 and 30. However, counting from 18 to 30, including 18 and 30, would give you 13 integers.
Commonly, 18 is subtracted from 30 to obtain the answer, which is false if the range is inclusive.
18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30
This error or misconception occurs because while subtracting 18 from 30, the 18th integer is not included in the count.
In continuation, you should read some of our other articles, like this one on – The 80/20 Rule For Your GRE Preparation
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