Finding the Fourth Proportional to 9,111.67, 13,666.42 and 3,187.60

Step by Step Solution

1. Step 1: Write the proportion equation
   9,111.67 : 13,666.42 = 3,187.60 : x
2. Step 2: Convert to fraction form
   9,111.67/13,666.42 = 3,187.60/x
3. Step 3: Cross multiply
   9,111.67x = 13,666.42 × 3,187.60
4. Step 4: Simplify right side
   9,111.67x = 43,563,080.39
5. Step 5: Solve for x
   x = 43,563,080.39/9,111.67
6. Step 6: Final answer
   x = 4,781.02