Add 42/21 and 72/45
1st number: 2 0/21, 2nd number: 1 27/45
42/21 + 72/45 is 18/5.
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,
42/21 = 42 × 15/21 × 15 = 630/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
72/45 = 72 × 7/45 × 7 = 504/315 - Add the two like fractions:
630/315 + 504/315 = 630 + 504/315 = 1134/315 - 1134/315 simplified gives 18/5
- So, 42/21 + 72/45 = 18/5
In mixed form: 33/5
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