Add 90/70 and 21/12
1st number: 1 20/70, 2nd number: 1 9/12
90/70 + 21/12 is 85/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420 - Add the two like fractions:
540/420 + 735/420 = 540 + 735/420 = 1275/420 - 1275/420 simplified gives 85/28
- So, 90/70 + 21/12 = 85/28
In mixed form: 31/28
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