Add 70/21 and 12/45
1st number: 3 7/21, 2nd number: 12/45
70/21 + 12/45 is 18/5.
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,
70/21 = 70 × 15/21 × 15 = 1050/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315 - Add the two like fractions:
1050/315 + 84/315 = 1050 + 84/315 = 1134/315 - 1134/315 simplified gives 18/5
- So, 70/21 + 12/45 = 18/5
In mixed form: 33/5
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