Add 5/21 and 15/45
5/21 + 15/45 is 4/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
5/21 = 5 × 15/21 × 15 = 75/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
15/45 = 15 × 7/45 × 7 = 105/315 - Add the two like fractions:
75/315 + 105/315 = 75 + 105/315 = 180/315 - 180/315 simplified gives 4/7
- So, 5/21 + 15/45 = 4/7
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