Add 20/21 and 70/15
1st number: 20/21, 2nd number: 4 10/15
20/21 + 70/15 is 118/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
70/15 = 70 × 7/15 × 7 = 490/105 - Add the two like fractions:
100/105 + 490/105 = 100 + 490/105 = 590/105 - 590/105 simplified gives 118/21
- So, 20/21 + 70/15 = 118/21
In mixed form: 513/21
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