Finding the Fourth Proportional to 13,124.61, 18,111.42 and 7,156.15

Step by Step Solution

1. Step 1: Write the proportion equation
   13,124.61 : 18,111.42 = 7,156.15 : x
2. Step 2: Convert to fraction form
   13,124.61/18,111.42 = 7,156.15/x
3. Step 3: Cross multiply
   13,124.61x = 18,111.42 × 7,156.15
4. Step 4: Simplify right side
   13,124.61x = 129,607,992.95
5. Step 5: Solve for x
   x = 129,607,992.95/13,124.61
6. Step 6: Final answer
   x = 9,875.19