Add 9/72 and 80/21, Solve 9/72 + 3 17/21 as a fraction

Add 9/72 and 80/21

1^st number: 9/72, 2^nd number: 3 17/21

9/72 + 80/21 is 661/168.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
9/72 = 9 × 7/72 × 7 = 63/504
Likewise, for the 2nd fraction, since 21 × 24 = 504,
80/21 = 80 × 24/21 × 24 = 1920/504
Add the two like fractions:
63/504 + 1920/504 = 63 + 1920/504 = 1983/504
1983/504 simplified gives 661/168
So, 9/72 + 80/21 = 661/168
In mixed form: 3157/168

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