Evaluate 2/5 of 3 1/2 + 4/5

Method 1: By Listing MultiplesList out all multiples of each denominator, and find the first common one. Multiples of 5 : 5, 10, 15, 20, ...

Multiples of 4 : 4, 8, 12, 16, 20, ...

Therefore, the LCD is 20 20 20. Method 2: By Prime FactorsList all prime factors of each denominator, and find the union of these primes. Prime Factors of 5 : 5

Prime Factors of 4 : 2, 2

Therefore, the LCD is 2*2*5=20 2/times 2/times 5=20 2*2*5=20.

2/5 of 3 1/2 + 4/5=

Answer: 2.2