Add 7/15 and 21/54
7/15 + 21/54 is 77/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 54 is 270
Next, find the equivalent fraction of both fractional numbers with denominator 270 - For the 1st fraction, since 15 × 18 = 270,
7/15 = 7 × 18/15 × 18 = 126/270 - Likewise, for the 2nd fraction, since 54 × 5 = 270,
21/54 = 21 × 5/54 × 5 = 105/270 - Add the two like fractions:
126/270 + 105/270 = 126 + 105/270 = 231/270 - 231/270 simplified gives 77/90
- So, 7/15 + 21/54 = 77/90
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