Add 90/40 and 30/21
1st number: 2 10/40, 2nd number: 1 9/21
90/40 + 30/21 is 103/28.
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,
30/21 = 30 × 40/21 × 40 = 1200/840 - Add the two like fractions:
1890/840 + 1200/840 = 1890 + 1200/840 = 3090/840 - 3090/840 simplified gives 103/28
- So, 90/40 + 30/21 = 103/28
In mixed form: 319/28
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