Add 21/42 and 80/45
1st number: 21/42, 2nd number: 1 35/45
21/42 + 80/45 is 41/18.
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,
21/42 = 21 × 15/42 × 15 = 315/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
80/45 = 80 × 14/45 × 14 = 1120/630 - Add the two like fractions:
315/630 + 1120/630 = 315 + 1120/630 = 1435/630 - 1435/630 simplified gives 41/18
- So, 21/42 + 80/45 = 41/18
In mixed form: 25/18
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