Add 21/7 and 20/45
1st number: 3 0/7, 2nd number: 20/45
21/7 + 20/45 is 31/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 7 × 45 = 315,
21/7 = 21 × 45/7 × 45 = 945/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Add the two like fractions:
945/315 + 140/315 = 945 + 140/315 = 1085/315 - 1085/315 simplified gives 31/9
- So, 21/7 + 20/45 = 31/9
In mixed form: 34/9
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