Add 30/21 and 15/40, Solve 1 9/21 + 15/40 as a fraction

Add 30/21 and 15/40

1^st number: 1 9/21, 2^nd number: 15/40

30/21 + 15/40 is 101/56.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
30/21 = 30 × 40/21 × 40 = 1200/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840
Add the two like fractions:
1200/840 + 315/840 = 1200 + 315/840 = 1515/840
1515/840 simplified gives 101/56
So, 30/21 + 15/40 = 101/56
In mixed form: 145/56

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