Add 4/45 and 20/21
4/45 + 20/21 is 328/315.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
4/45 = 4 × 7/45 × 7 = 28/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
20/21 = 20 × 15/21 × 15 = 300/315 - Add the two like fractions:
28/315 + 300/315 = 28 + 300/315 = 328/315 - So, 4/45 + 20/21 = 328/315
In mixed form: 113/315
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