Add 20/36 and 21/70
20/36 + 21/70 is 77/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 70 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 36 × 35 = 1260,
20/36 = 20 × 35/36 × 35 = 700/1260 - Likewise, for the 2nd fraction, since 70 × 18 = 1260,
21/70 = 21 × 18/70 × 18 = 378/1260 - Add the two like fractions:
700/1260 + 378/1260 = 700 + 378/1260 = 1078/1260 - 1078/1260 simplified gives 77/90
- So, 20/36 + 21/70 = 77/90
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