Add 4/21 and 70/40, Solve 4/21 + 1 30/40 as a fraction

Add 4/21 and 70/40

1^st number: 4/21, 2^nd number: 1 30/40

4/21 + 70/40 is 163/84.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
4/21 = 4 × 40/21 × 40 = 160/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840
Add the two like fractions:
160/840 + 1470/840 = 160 + 1470/840 = 1630/840
1630/840 simplified gives 163/84
So, 4/21 + 70/40 = 163/84
In mixed form: 179/84

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