Add 21/70 and 8/90
21/70 + 8/90 is 7/18.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
8/90 = 8 × 7/90 × 7 = 56/630 - Add the two like fractions:
189/630 + 56/630 = 189 + 56/630 = 245/630 - 245/630 simplified gives 7/18
- So, 21/70 + 8/90 = 7/18
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