Add 21/10 and 90/72
1st number: 2 1/10, 2nd number: 1 18/72
21/10 + 90/72 is 67/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 10 × 36 = 360,
21/10 = 21 × 36/10 × 36 = 756/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
90/72 = 90 × 5/72 × 5 = 450/360 - Add the two like fractions:
756/360 + 450/360 = 756 + 450/360 = 1206/360 - 1206/360 simplified gives 67/20
- So, 21/10 + 90/72 = 67/20
In mixed form: 37/20
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