Add 42/21 and 12/45
1st number: 2 0/21, 2nd number: 12/45
42/21 + 12/45 is 34/15.
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,
42/21 = 42 × 15/21 × 15 = 630/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315 - Add the two like fractions:
630/315 + 84/315 = 630 + 84/315 = 714/315 - 714/315 simplified gives 34/15
- So, 42/21 + 12/45 = 34/15
In mixed form: 24/15
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