Add 45/12 and 21/70
1st number: 3 9/12, 2nd number: 21/70
45/12 + 21/70 is 81/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 12 × 35 = 420,
45/12 = 45 × 35/12 × 35 = 1575/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420 - Add the two like fractions:
1575/420 + 126/420 = 1575 + 126/420 = 1701/420 - 1701/420 simplified gives 81/20
- So, 45/12 + 21/70 = 81/20
In mixed form: 41/20
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