1. The problem is to add the two fractions $\frac{20}{15}$ and $\frac{4}{2}$.\n\n2. To add fractions, they must have a common denominator. The denominators here are 15 and 2.\n\n3. Find the least common denominator (LCD) of 15 and 2. Since 15 = 3 \times 5 and 2 is prime, the LCD is $15 \times 2 = 30$.\n\n4. Convert each fraction to an equivalent fraction with denominator 30:\n\n$$\frac{20}{15} = \frac{20 \times 2}{15 \times 2} = \frac{40}{30}$$\n$$\frac{4}{2} = \frac{4 \times 15}{2 \times 15} = \frac{60}{30}$$\n\n5. Now add the fractions:\n\n$$\frac{40}{30} + \frac{60}{30} = \frac{40 + 60}{30} = \frac{100}{30}$$\n\n6. Simplify the fraction $\frac{100}{30}$ by dividing numerator and denominator by their greatest common divisor (GCD), which is 10:\n\n$$\frac{100 \div 10}{30 \div 10} = \frac{10}{3}$$\n\n7. The final answer is $\frac{10}{3}$ or as a mixed number $3 \frac{1}{3}$.