Finding the Fourth Proportional to 12,390.76, 18,588.42 and 4,071.24

Step by Step Solution

1. Step 1: Write the proportion equation
   12,390.76 : 18,588.42 = 4,071.24 : x
2. Step 2: Convert to fraction form
   12,390.76/18,588.42 = 4,071.24/x
3. Step 3: Cross multiply
   12,390.76x = 18,588.42 × 4,071.24
4. Step 4: Simplify right side
   12,390.76x = 75,677,919.04
5. Step 5: Solve for x
   x = 75,677,919.04/12,390.76
6. Step 6: Final answer
   x = 6,107.61