Finding the Fourth Proportional to 2,609.69, 3,913.83 and 1,221.67

Step by Step Solution

1. Step 1: Write the proportion equation
   2,609.69 : 3,913.83 = 1,221.67 : x
2. Step 2: Convert to fraction form
   2,609.69/3,913.83 = 1,221.67/x
3. Step 3: Cross multiply
   2,609.69x = 3,913.83 × 1,221.67
4. Step 4: Simplify right side
   2,609.69x = 4,781,408.70
5. Step 5: Solve for x
   x = 4,781,408.70/2,609.69
6. Step 6: Final answer
   x = 1,832.17