Add 21/70 and 80/40
1st number: 21/70, 2nd number: 2 0/40
21/70 + 80/40 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
80/40 = 80 × 7/40 × 7 = 560/280 - Add the two like fractions:
84/280 + 560/280 = 84 + 560/280 = 644/280 - 644/280 simplified gives 23/10
- So, 21/70 + 80/40 = 23/10
In mixed form: 23/10
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