Add 28/7 and 21/40
1st number: 4 0/7, 2nd number: 21/40
28/7 + 21/40 is 181/40.
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,
28/7 = 28 × 40/7 × 40 = 1120/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Add the two like fractions:
1120/280 + 147/280 = 1120 + 147/280 = 1267/280 - 1267/280 simplified gives 181/40
- So, 28/7 + 21/40 = 181/40
In mixed form: 421/40
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