Add 9/45 and 40/21, Solve 9/45 + 1 19/21 as a fraction

Add 9/45 and 40/21

1^st number: 9/45, 2^nd number: 1 19/21

9/45 + 40/21 is 221/105.

Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 45 × 7 = 315,
9/45 = 9 × 7/45 × 7 = 63/315
Likewise, for the 2nd fraction, since 21 × 15 = 315,
40/21 = 40 × 15/21 × 15 = 600/315
Add the two like fractions:
63/315 + 600/315 = 63 + 600/315 = 663/315
663/315 simplified gives 221/105
So, 9/45 + 40/21 = 221/105
In mixed form: 211/105

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