Add 42/45 and 70/21
1st number: 42/45, 2nd number: 3 7/21
42/45 + 70/21 is 64/15.
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,
42/45 = 42 × 7/45 × 7 = 294/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
70/21 = 70 × 15/21 × 15 = 1050/315 - Add the two like fractions:
294/315 + 1050/315 = 294 + 1050/315 = 1344/315 - 1344/315 simplified gives 64/15
- So, 42/45 + 70/21 = 64/15
In mixed form: 44/15
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