Add 28/21 and 9/60, Solve 1 7/21 + 9/60 as a fraction

Add 28/21 and 9/60

1^st number: 1 7/21, 2^nd number: 9/60

28/21 + 9/60 is 89/60.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420
Likewise, for the 2nd fraction, since 60 × 7 = 420,
9/60 = 9 × 7/60 × 7 = 63/420
Add the two like fractions:
560/420 + 63/420 = 560 + 63/420 = 623/420
623/420 simplified gives 89/60
So, 28/21 + 9/60 = 89/60
In mixed form: 129/60

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