Add 70/21 and 63/20
1st number: 3 7/21, 2nd number: 3 3/20
70/21 + 63/20 is 389/60.
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,
63/20 = 63 × 21/20 × 21 = 1323/420 - Add the two like fractions:
1400/420 + 1323/420 = 1400 + 1323/420 = 2723/420 - 2723/420 simplified gives 389/60
- So, 70/21 + 63/20 = 389/60
In mixed form: 629/60
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