Add 60/40 and 28/21, Solve 1 20/40 + 1 7/21 as a fraction

Add 60/40 and 28/21

1^st number: 1 20/40, 2^nd number: 1 7/21

60/40 + 28/21 is 17/6.

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,
60/40 = 60 × 21/40 × 21 = 1260/840
Likewise, for the 2nd fraction, since 21 × 40 = 840,
28/21 = 28 × 40/21 × 40 = 1120/840
Add the two like fractions:
1260/840 + 1120/840 = 1260 + 1120/840 = 2380/840
2380/840 simplified gives 17/6
So, 60/40 + 28/21 = 17/6
In mixed form: 25/6

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