Add 21/42 and 90/45
1st number: 21/42, 2nd number: 2 0/45
21/42 + 90/45 is 5/2.
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,
90/45 = 90 × 14/45 × 14 = 1260/630 - Add the two like fractions:
315/630 + 1260/630 = 315 + 1260/630 = 1575/630 - 1575/630 simplified gives 5/2
- So, 21/42 + 90/45 = 5/2
In mixed form: 21/2
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