Add 28/90 and 70/42
1st number: 28/90, 2nd number: 1 28/42
28/90 + 70/42 is 89/45.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
28/90 = 28 × 7/90 × 7 = 196/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
70/42 = 70 × 15/42 × 15 = 1050/630 - Add the two like fractions:
196/630 + 1050/630 = 196 + 1050/630 = 1246/630 - 1246/630 simplified gives 89/45
- So, 28/90 + 70/42 = 89/45
In mixed form: 144/45
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