Add 28/21 and 25/40, Solve 1 7/21 + 25/40 as a fraction

Add 28/21 and 25/40

1^st number: 1 7/21, 2^nd number: 25/40

28/21 + 25/40 is 47/24.

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,
28/21 = 28 × 40/21 × 40 = 1120/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
25/40 = 25 × 21/40 × 21 = 525/840
Add the two like fractions:
1120/840 + 525/840 = 1120 + 525/840 = 1645/840
1645/840 simplified gives 47/24
So, 28/21 + 25/40 = 47/24
In mixed form: 123/24

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