Add 72/42 and 20/45
1st number: 1 30/42, 2nd number: 20/45
72/42 + 20/45 is 136/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
72/42 = 72 × 15/42 × 15 = 1080/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630 - Add the two like fractions:
1080/630 + 280/630 = 1080 + 280/630 = 1360/630 - 1360/630 simplified gives 136/63
- So, 72/42 + 20/45 = 136/63
In mixed form: 210/63
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