Add 8/21 and 15/45
8/21 + 15/45 is 5/7.
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,
8/21 = 8 × 15/21 × 15 = 120/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
15/45 = 15 × 7/45 × 7 = 105/315 - Add the two like fractions:
120/315 + 105/315 = 120 + 105/315 = 225/315 - 225/315 simplified gives 5/7
- So, 8/21 + 15/45 = 5/7
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