Add 7/8 and 21/70
7/8 + 21/70 is 47/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 8 × 35 = 280,
7/8 = 7 × 35/8 × 35 = 245/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Add the two like fractions:
245/280 + 84/280 = 245 + 84/280 = 329/280 - 329/280 simplified gives 47/40
- So, 7/8 + 21/70 = 47/40
In mixed form: 17/40
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