Add 28/21 and 72/90
1st number: 1 7/21, 2nd number: 72/90
28/21 + 72/90 is 32/15.
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,
72/90 = 72 × 7/90 × 7 = 504/630 - Add the two like fractions:
840/630 + 504/630 = 840 + 504/630 = 1344/630 - 1344/630 simplified gives 32/15
- So, 28/21 + 72/90 = 32/15
In mixed form: 22/15
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