Add 45/90 and 5/21
45/90 + 5/21 is 31/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
45/90 = 45 × 7/90 × 7 = 315/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
5/21 = 5 × 30/21 × 30 = 150/630 - Add the two like fractions:
315/630 + 150/630 = 315 + 150/630 = 465/630 - 465/630 simplified gives 31/42
- So, 45/90 + 5/21 = 31/42
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