Add 70/90 and 5/21
70/90 + 5/21 is 64/63.
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,
70/90 = 70 × 7/90 × 7 = 490/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
5/21 = 5 × 30/21 × 30 = 150/630 - Add the two like fractions:
490/630 + 150/630 = 490 + 150/630 = 640/630 - 640/630 simplified gives 64/63
- So, 70/90 + 5/21 = 64/63
In mixed form: 11/63
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