Quant Essentials Flashcards
Method # 1 for simplifying complex fractions
Multiply BOTH the numerator and the denominator of the complex fraction by the LCD
Method # 2 for simplifying complex fractions
Write the numerator and the denominator as single fractions and then divide
Method # 3 for simplifying complex fractions
The product of the means is the the denominator and the product of the extremes is the numerator. The numbers on the “outside” are the extremes. Ex: the first numerator x the second denominator. The inside numbers are the second denominator and the second numerator. Those are the means. So if a,b,c, and d are nonzero, then when a/b is divided by c/d, the denominator of the quotient will be the product of the means, and the numerator of the quotient will be the product of the extremes.
Bow tie method for comparing the size of fractions
Two positive fractions, A and B. Multiply the denominator of B by the numerator if A and vice verse. The larger product is over the larger fraction.
Comparing fraction size with a common denominator
The larger the numerator, the larger the fraction.
Comparing fraction size with a common numerator
The larger the denominator, the smaller the fraction.
To get the reciprocal of a nonzero number
Divide 1 by that number. Also remember that the product of a number and its reciprocal is 1.
How to obtain “1 over a fraction”
Flip the numerator and the denominator of the fraction.
Perfect squares never end in
2, 3, 7, or 8. It will end with 0, 1, 4, 5, 6, or 9.
PEMDAS variation # 1
If the operations involved are only addition and subtraction, we don’t really have to add and subtract from left to right. We can just combine like terms as we do in Algebra. As long as we combine them along with their signs, we don’t need to follow the left to right order.
PEMDAS variation # 2
Recall that in algebra, terms are separated by a plus or a minus son that is outside of the parentheses. You can simplify each term separately or simultaneously.
Two unique features of factorials
0!=1 and 1!=1
