Add 21/8 and 54/90
1st number: 2 5/8, 2nd number: 54/90
21/8 + 54/90 is 129/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 8 × 45 = 360,
21/8 = 21 × 45/8 × 45 = 945/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
54/90 = 54 × 4/90 × 4 = 216/360 - Add the two like fractions:
945/360 + 216/360 = 945 + 216/360 = 1161/360 - 1161/360 simplified gives 129/40
- So, 21/8 + 54/90 = 129/40
In mixed form: 39/40
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