Add 21/90 and 30/70
21/90 + 30/70 is 139/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
30/70 = 30 × 9/70 × 9 = 270/630 - Add the two like fractions:
147/630 + 270/630 = 147 + 270/630 = 417/630 - 417/630 simplified gives 139/210
- So, 21/90 + 30/70 = 139/210
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