GMAT 01 - Fractions & Decimals Flashcards
3/8 + 1/2 = ?
LCD = 8
= 7/8
3 + 1/4 = ?
3 + 1/4 = 3 1/4
= 13/4
Fractions within the Denominator trick
Fractions that contain a fraction in the denominator can be simplified by putting the numerator over one and multiplying the numerator by the “flip” of the denominator
example:
2/(1/3)
= (2/1) / (1/3)
= (2/1) x (3/1)
= 6
5/7 - 1/3 = ?
LCD = 21
= 8/21
Simplify the Fraction:
75/300
= 1/4
( 75/300 = (3x25) / (3x100) = 25/100 )
( 25/100 = (1x25) / (4x25) = 1/4 )
This fraction breaks down twice
How do you convert a fraction into a mixed numeral?
1) Divide the numerator by the denominator. The number of times that the denominator can go into the numerator determines the whole number portion of the mixed numeral
2) Place the remainder over the denominator. The resulting fraction is the fractional portion of the mixed numeral.
5/7 - 2/7 = ?
= 3/7
(y/4) / (y/x) = ?
= x/4
(y/4) / (y/x) = (y/4) x (x/y)
(y’s eliminate)
= (1/4) x (x/1)
= x/4
(2a/3b) / 2ac = ?
= 1/3bc
(2a/3b) / 2ac
= (2a/3b) / (2ac/1)
= (2a/3b) x (1/2ac)
= 2a/6abc
= 1/3bc
3 3/4 x 7 1/3 = ?
= 55/2
3 3/4 x 7 1/3
= (12/4)+(3/4) x (21/3)+(1/3)
= 15/4 x 22/3
(common denominator = 4x3 = 12)
6 / (4x-x) = ?
= 2/x
6 / (4x-x)
= (2)(3) / (3x)
= 2/x
X - 1/4 = ?
LCD = 4
= (4x-1)/4


1/5 + 2/5 =
= 3/5
(ab2c)/(abc) x (ac)/(abc) = ?
= 1
(ab2c)/(abc) x (ac)/(abc)
= b(abc)/(abc) x (ac)/(abc)
= (b)/1 x (ac)/abc)
= abc/abc
= 1
4 - 1/5 = ?
LCD = 5
= 19/5
14/9 x 6/21 = ?
= 4/9
14/9 x 6/21 = (2x7)/(3x3) x (3x2)/(3x7)
7s and one set of 3s cancel
= (2/3) x (2/3)
= 4/9
6 + 2/x = ?
6 + 2/x = 6 2/x = (6x + 2) / x
Simplify the Fraction:
14/98
= 1/7
( 14/98 = (2x7) / (2x49) = 7/49 )
( 7/49 = (1x7) / (7x7) = 1/7 )
This fraction breaks down twice
7 1/4 - 4 1/2 = ?
= 11/4
7 1/4 - 4 1/2
= (28/4)+(1/4) - (8/2)+(1/2)
= 29/4 - 9/2
(common denominator = 4)
29/4 - (2/2)(9/2)
= 29/4 - 18/4
= 11/4
Fractions within the Numerator Trick
Fractions that contain a fraction in the numerator can be simplified by putting the denominator over one and multiplying the numerator by the “flip” of the denominator
Example:
(2/3)/4
= (2/3) / (4/1)
= (2/3) x (1/4)
= 2/12
= 1/6
Convert into a Mixed Fraction:
38/7
= 5 3/7
( 38/7 = 5 remainder 3)
Convert into a Mixed Fraction:
25/4
= 6 1/4
(25/4 = 6 remainder 1)
(11-1) / (2+3) = ?
= 2
(11-1) / (2+3)
= 10/5
= 2













