Add 7/21 and 40/45
7/21 + 40/45 is 11/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
7/21 = 7 × 15/21 × 15 = 105/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
40/45 = 40 × 7/45 × 7 = 280/315 - Add the two like fractions:
105/315 + 280/315 = 105 + 280/315 = 385/315 - 385/315 simplified gives 11/9
- So, 7/21 + 40/45 = 11/9
In mixed form: 12/9
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