Add 15/8 and 81/40, Solve 1 7/8 + 2 1/40 as a fraction

Add 15/8 and 81/40

1^st number: 1 7/8, 2^nd number: 2 1/40

15/8 + 81/40 is 39/10.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 40 is 40

Next, find the equivalent fraction of both fractional numbers with denominator 40
For the 1st fraction, since 8 × 5 = 40,
15/8 = 15 × 5/8 × 5 = 75/40
Likewise, for the 2nd fraction, since 40 × 1 = 40,
81/40 = 81 × 1/40 × 1 = 81/40
Add the two like fractions:
75/40 + 81/40 = 75 + 81/40 = 156/40
156/40 simplified gives 39/10
So, 15/8 + 81/40 = 39/10
In mixed form: 39/10

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