Add 70/45 and 80/21
1st number: 1 25/45, 2nd number: 3 17/21
70/45 + 80/21 is 338/63.
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,
70/45 = 70 × 7/45 × 7 = 490/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
80/21 = 80 × 15/21 × 15 = 1200/315 - Add the two like fractions:
490/315 + 1200/315 = 490 + 1200/315 = 1690/315 - 1690/315 simplified gives 338/63
- So, 70/45 + 80/21 = 338/63
In mixed form: 523/63
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