Add 30/21 and 81/40
1st number: 1 9/21, 2nd number: 2 1/40
30/21 + 81/40 is 967/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
30/21 = 30 × 40/21 × 40 = 1200/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
81/40 = 81 × 21/40 × 21 = 1701/840 - Add the two like fractions:
1200/840 + 1701/840 = 1200 + 1701/840 = 2901/840 - 2901/840 simplified gives 967/280
- So, 30/21 + 81/40 = 967/280
In mixed form: 3127/280
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