Add 21/36 and 20/90
21/36 + 20/90 is 29/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 36 × 5 = 180,
21/36 = 21 × 5/36 × 5 = 105/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
20/90 = 20 × 2/90 × 2 = 40/180 - Add the two like fractions:
105/180 + 40/180 = 105 + 40/180 = 145/180 - 145/180 simplified gives 29/36
- So, 21/36 + 20/90 = 29/36
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