Finding the Fourth Proportional to 1,111.12, 1,665.12 and 866.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.12 : 1,665.12 = 866.56 : x
2. Step 2: Convert to fraction form
   1,111.12/1,665.12 = 866.56/x
3. Step 3: Cross multiply
   1,111.12x = 1,665.12 × 866.56
4. Step 4: Simplify right side
   1,111.12x = 1,442,926.39
5. Step 5: Solve for x
   x = 1,442,926.39/1,111.12
6. Step 6: Final answer
   x = 1,298.62