Add 28/21 and 70/90
1st number: 1 7/21, 2nd number: 70/90
28/21 + 70/90 is 19/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
28/21 = 28 × 30/21 × 30 = 840/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630 - Add the two like fractions:
840/630 + 490/630 = 840 + 490/630 = 1330/630 - 1330/630 simplified gives 19/9
- So, 28/21 + 70/90 = 19/9
In mixed form: 21/9
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