Add 90/21 and 14/40, Solve 4 6/21 + 14/40 as a fraction

Add 90/21 and 14/40

1^st number: 4 6/21, 2^nd number: 14/40

90/21 + 14/40 is 649/140.

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,
90/21 = 90 × 40/21 × 40 = 3600/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
14/40 = 14 × 21/40 × 21 = 294/840
Add the two like fractions:
3600/840 + 294/840 = 3600 + 294/840 = 3894/840
3894/840 simplified gives 649/140
So, 90/21 + 14/40 = 649/140
In mixed form: 489/140

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