Add 90/40 and 15/21
1st number: 2 10/40, 2nd number: 15/21
90/40 + 15/21 is 83/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
90/40 = 90 × 21/40 × 21 = 1890/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
15/21 = 15 × 40/21 × 40 = 600/840 - Add the two like fractions:
1890/840 + 600/840 = 1890 + 600/840 = 2490/840 - 2490/840 simplified gives 83/28
- So, 90/40 + 15/21 = 83/28
In mixed form: 227/28
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