Add 28/42 and 72/90
28/42 + 72/90 is 22/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
28/42 = 28 × 15/42 × 15 = 420/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Add the two like fractions:
420/630 + 504/630 = 420 + 504/630 = 924/630 - 924/630 simplified gives 22/15
- So, 28/42 + 72/90 = 22/15
In mixed form: 17/15
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