Add 7/20 and 21/72
7/20 + 21/72 is 77/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
7/20 = 7 × 18/20 × 18 = 126/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
21/72 = 21 × 5/72 × 5 = 105/360 - Add the two like fractions:
126/360 + 105/360 = 126 + 105/360 = 231/360 - 231/360 simplified gives 77/120
- So, 7/20 + 21/72 = 77/120
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