Add 21/35 and 42/45
21/35 + 42/45 is 23/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 35 × 9 = 315,
21/35 = 21 × 9/35 × 9 = 189/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
42/45 = 42 × 7/45 × 7 = 294/315 - Add the two like fractions:
189/315 + 294/315 = 189 + 294/315 = 483/315 - 483/315 simplified gives 23/15
- So, 21/35 + 42/45 = 23/15
In mixed form: 18/15
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