Add 6/21 and 42/45
6/21 + 42/45 is 128/105.
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,
6/21 = 6 × 15/21 × 15 = 90/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315 - Add the two like fractions:
90/315 + 294/315 = 90 + 294/315 = 384/315 - 384/315 simplified gives 128/105
- So, 6/21 + 42/45 = 128/105
In mixed form: 123/105
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