Add 28/21 and 5/40, Solve 1 7/21 + 5/40 as a fraction

Add 28/21 and 5/40

1^st number: 1 7/21, 2^nd number: 5/40

28/21 + 5/40 is 35/24.

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,
5/40 = 5 × 21/40 × 21 = 105/840
Add the two like fractions:
1120/840 + 105/840 = 1120 + 105/840 = 1225/840
1225/840 simplified gives 35/24
So, 28/21 + 5/40 = 35/24
In mixed form: 111/24

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