Add 72/64 and 42/20
1st number: 1 8/64, 2nd number: 2 2/20
72/64 + 42/20 is 129/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 64 and 20 is 320
Next, find the equivalent fraction of both fractional numbers with denominator 320 - For the 1st fraction, since 64 × 5 = 320,
72/64 = 72 × 5/64 × 5 = 360/320 - Likewise, for the 2nd fraction, since 20 × 16 = 320,
42/20 = 42 × 16/20 × 16 = 672/320 - Add the two like fractions:
360/320 + 672/320 = 360 + 672/320 = 1032/320 - 1032/320 simplified gives 129/40
- So, 72/64 + 42/20 = 129/40
In mixed form: 39/40
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