Add 21/45 and 15/63
21/45 + 15/63 is 74/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 63 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 63 × 5 = 315,
15/63 = 15 × 5/63 × 5 = 75/315 - Add the two like fractions:
147/315 + 75/315 = 147 + 75/315 = 222/315 - 222/315 simplified gives 74/105
- So, 21/45 + 15/63 = 74/105
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