Add 70/21 and 4/45, Solve 3 7/21 + 4/45 as a fraction

Add 70/21 and 4/45

1^st number: 3 7/21, 2^nd number: 4/45

70/21 + 4/45 is 154/45.

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

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
70/21 = 70 × 15/21 × 15 = 1050/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
4/45 = 4 × 7/45 × 7 = 28/315
Add the two like fractions:
1050/315 + 28/315 = 1050 + 28/315 = 1078/315
1078/315 simplified gives 154/45
So, 70/21 + 4/45 = 154/45
In mixed form: 319/45

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