Finding the Fourth Proportional to 3,978.74, 5,490.23 and 2,385.06

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978.74 : 5,490.23 = 2,385.06 : x
2. Step 2: Convert to fraction form
   3,978.74/5,490.23 = 2,385.06/x
3. Step 3: Cross multiply
   3,978.74x = 5,490.23 × 2,385.06
4. Step 4: Simplify right side
   3,978.74x = 13,094,516.04
5. Step 5: Solve for x
   x = 13,094,516.04/3,978.74
6. Step 6: Final answer
   x = 3,291.13