Add 5/21 and 40/45
5/21 + 40/45 is 71/63.
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,
5/21 = 5 × 15/21 × 15 = 75/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
40/45 = 40 × 7/45 × 7 = 280/315 - Add the two like fractions:
75/315 + 280/315 = 75 + 280/315 = 355/315 - 355/315 simplified gives 71/63
- So, 5/21 + 40/45 = 71/63
In mixed form: 18/63
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