Finding the Fourth Proportional to 12,887, 17,753.70 and 12,111.98

Step by Step Solution

1. Step 1: Write the proportion equation
   12,887 : 17,753.70 = 12,111.98 : x
2. Step 2: Convert to fraction form
   12,887/17,753.70 = 12,111.98/x
3. Step 3: Cross multiply
   12,887x = 17,753.70 × 12,111.98
4. Step 4: Simplify right side
   12,887x = 215,032,459.33
5. Step 5: Solve for x
   x = 215,032,459.33/12,887
6. Step 6: Final answer
   x = 16,686.00