Add 70/21 and 45/20
1st number: 3 7/21, 2nd number: 2 5/20
70/21 + 45/20 is 67/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
70/21 = 70 × 20/21 × 20 = 1400/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
45/20 = 45 × 21/20 × 21 = 945/420 - Add the two like fractions:
1400/420 + 945/420 = 1400 + 945/420 = 2345/420 - 2345/420 simplified gives 67/12
- So, 70/21 + 45/20 = 67/12
In mixed form: 57/12
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