Add 21/7 and 18/40
1st number: 3 0/7, 2nd number: 18/40
21/7 + 18/40 is 69/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
21/7 = 21 × 40/7 × 40 = 840/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
18/40 = 18 × 7/40 × 7 = 126/280 - Add the two like fractions:
840/280 + 126/280 = 840 + 126/280 = 966/280 - 966/280 simplified gives 69/20
- So, 21/7 + 18/40 = 69/20
In mixed form: 39/20
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