Add 28/21 and 90/60
1st number: 1 7/21, 2nd number: 1 30/60
28/21 + 90/60 is 17/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
90/60 = 90 × 7/60 × 7 = 630/420 - Add the two like fractions:
560/420 + 630/420 = 560 + 630/420 = 1190/420 - 1190/420 simplified gives 17/6
- So, 28/21 + 90/60 = 17/6
In mixed form: 25/6
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