Add 20/40 and 21/7
1st number: 20/40, 2nd number: 3 0/7
20/40 + 21/7 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
20/40 = 20 × 7/40 × 7 = 140/280 - Likewise, for the 2nd fraction, since 7 × 40 = 280,
21/7 = 21 × 40/7 × 40 = 840/280 - Add the two like fractions:
140/280 + 840/280 = 140 + 840/280 = 980/280 - 980/280 simplified gives 7/2
- So, 20/40 + 21/7 = 7/2
In mixed form: 31/2
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