Add 21/80 and 84/60, Solve 21/80 + 1 24/60 as a fraction

Add 21/80 and 84/60

1^st number: 21/80, 2^nd number: 1 24/60

21/80 + 84/60 is 133/80.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 60 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 80 × 3 = 240,
21/80 = 21 × 3/80 × 3 = 63/240
Likewise, for the 2nd fraction, since 60 × 4 = 240,
84/60 = 84 × 4/60 × 4 = 336/240
Add the two like fractions:
63/240 + 336/240 = 63 + 336/240 = 399/240
399/240 simplified gives 133/80
So, 21/80 + 84/60 = 133/80
In mixed form: 153/80

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