Add 20/21 and 42/45
20/21 + 42/45 is 66/35.
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,
20/21 = 20 × 15/21 × 15 = 300/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315 - Add the two like fractions:
300/315 + 294/315 = 300 + 294/315 = 594/315 - 594/315 simplified gives 66/35
- So, 20/21 + 42/45 = 66/35
In mixed form: 131/35
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