Add 21/45 and 18/63
21/45 + 18/63 is 79/105.
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,
18/63 = 18 × 5/63 × 5 = 90/315 - Add the two like fractions:
147/315 + 90/315 = 147 + 90/315 = 237/315 - 237/315 simplified gives 79/105
- So, 21/45 + 18/63 = 79/105
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