Add 90/70 and 60/72, Solve 1 20/70 + 60/72 as a fraction

Add 90/70 and 60/72

1^st number: 1 20/70, 2^nd number: 60/72

90/70 + 60/72 is 89/42.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 70 × 36 = 2520,
90/70 = 90 × 36/70 × 36 = 3240/2520
Likewise, for the 2nd fraction, since 72 × 35 = 2520,
60/72 = 60 × 35/72 × 35 = 2100/2520
Add the two like fractions:
3240/2520 + 2100/2520 = 3240 + 2100/2520 = 5340/2520
5340/2520 simplified gives 89/42
So, 90/70 + 60/72 = 89/42
In mixed form: 25/42

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