Add 72/90 and 21/8
1st number: 72/90, 2nd number: 2 5/8
72/90 + 21/8 is 137/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 8 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
72/90 = 72 × 4/90 × 4 = 288/360 - Likewise, for the 2nd fraction, since 8 × 45 = 360,
21/8 = 21 × 45/8 × 45 = 945/360 - Add the two like fractions:
288/360 + 945/360 = 288 + 945/360 = 1233/360 - 1233/360 simplified gives 137/40
- So, 72/90 + 21/8 = 137/40
In mixed form: 317/40
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