Solve: (1/4 × 4/5) + 11/20 | Mixed Fraction Operations

To solve this problem, we'll approach it in the following steps:

Step 1: Perform the Multiplication
The expression begins with multiplying two fractions: $\frac{1}{4} \times \frac{4}{5}$. Using the formula for multiplying fractions, we get:
$\frac{1 \times 4}{4 \times 5} = \frac{4}{20}$
Simplifying $\frac{4}{20}$ by dividing both numerator and denominator by 4 gives:
$\frac{1}{5}$

Step 2: Add the Result to the Second Fraction
Now, we need to add $\frac{1}{5}$ to $\frac{11}{20}$. To do this, we first find a common denominator.
The least common denominator between 5 and 20 is 20. Convert $\frac{1}{5}$ to twentieths:
$\frac{1}{5} = \frac{4}{20}$
Now add $\frac{4}{20}$ to $\frac{11}{20}$:
$\frac{4}{20} + \frac{11}{20} = \frac{15}{20}$

Step 3: Simplify the Final Result
Simplify $\frac{15}{20}$ by dividing the numerator and the denominator by 5:
$\frac{15 \div 5}{20 \div 5} = \frac{3}{4}$

Therefore, the solution to the problem is $\frac{3}{4}$. This matches choice 1, which is $\frac{3}{4}$.