Add 12/5 and 70/21
1st number: 2 2/5, 2nd number: 3 7/21
12/5 + 70/21 is 86/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
12/5 = 12 × 21/5 × 21 = 252/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
70/21 = 70 × 5/21 × 5 = 350/105 - Add the two like fractions:
252/105 + 350/105 = 252 + 350/105 = 602/105 - 602/105 simplified gives 86/15
- So, 12/5 + 70/21 = 86/15
In mixed form: 511/15
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