20 years ago my age was `1/3` of what it is now. What is my present age ?

Options

A. 30 years
B. 25 years
C. 35 years
D. 40 years

Answer

To solve the problem step by step, let's denote the present age as \( X \).

### Step 1: Define the present age
Let the present age be \( X \).

### Step 2: Determine the age 20 years ago
20 years ago, the age would be \( X - 20 \).

### Step 3: Set up the equation based on the problem statement
According to the problem, 20 years ago, my age was \( \frac{1}{3} \) of what it is now. Therefore, we can write the equation as:
\[ X - 20 = \frac{1}{3}X \]

### Step 4: Eliminate the fraction
To eliminate the fraction, we can multiply both sides of the equation by 3:
\[ 3(X - 20) = X \]

### Step 5: Distribute on the left side
Distributing the 3 on the left side gives us:
\[ 3X - 60 = X \]

### Step 6: Rearrange the equation
Now, we will rearrange the equation to isolate \( X \):
\[ 3X - X = 60 \]
This simplifies to:
\[ 2X = 60 \]

### Step 7: Solve for \( X \)
Now, divide both sides by 2 to find \( X \):
\[ X = \frac{60}{2} = 30 \]

### Conclusion
The present age is \( 30 \) years.