Add 70/80 and 21/18
1st number: 70/80, 2nd number: 1 3/18
70/80 + 21/18 is 49/24.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
70/80 = 70 × 9/80 × 9 = 630/720 - Likewise, for the 2nd fraction, since 18 × 40 = 720,
21/18 = 21 × 40/18 × 40 = 840/720 - Add the two like fractions:
630/720 + 840/720 = 630 + 840/720 = 1470/720 - 1470/720 simplified gives 49/24
- So, 70/80 + 21/18 = 49/24
In mixed form: 21/24
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