Finding the Fourth Proportional to 3,783.69, 5,221.62 and 2,105.13

Step by Step Solution

1. Step 1: Write the proportion equation
   3,783.69 : 5,221.62 = 2,105.13 : x
2. Step 2: Convert to fraction form
   3,783.69/5,221.62 = 2,105.13/x
3. Step 3: Cross multiply
   3,783.69x = 5,221.62 × 2,105.13
4. Step 4: Simplify right side
   3,783.69x = 10,992,188.91
5. Step 5: Solve for x
   x = 10,992,188.91/3,783.69
6. Step 6: Final answer
   x = 2,905.15