Add 70/80 and 21/54
70/80 + 21/54 is 91/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 54 is 2160
Next, find the equivalent fraction of both fractional numbers with denominator 2160 - For the 1st fraction, since 80 × 27 = 2160,
70/80 = 70 × 27/80 × 27 = 1890/2160 - Likewise, for the 2nd fraction, since 54 × 40 = 2160,
21/54 = 21 × 40/54 × 40 = 840/2160 - Add the two like fractions:
1890/2160 + 840/2160 = 1890 + 840/2160 = 2730/2160 - 2730/2160 simplified gives 91/72
- So, 70/80 + 21/54 = 91/72
In mixed form: 119/72
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