Add 28/42 and 40/90
28/42 + 40/90 is 10/9.
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,
40/90 = 40 × 7/90 × 7 = 280/630 - Add the two like fractions:
420/630 + 280/630 = 420 + 280/630 = 700/630 - 700/630 simplified gives 10/9
- So, 28/42 + 40/90 = 10/9
In mixed form: 11/9
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