Add 30/90 and 3/21
30/90 + 3/21 is 10/21.
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,
30/90 = 30 × 7/90 × 7 = 210/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
3/21 = 3 × 30/21 × 30 = 90/630 - Add the two like fractions:
210/630 + 90/630 = 210 + 90/630 = 300/630 - 300/630 simplified gives 10/21
- So, 30/90 + 3/21 = 10/21
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