Finding the Fourth Proportional to 1,315.09, 1,815.01 and 866.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,315.09 : 1,815.01 = 866.89 : x
2. Step 2: Convert to fraction form
   1,315.09/1,815.01 = 866.89/x
3. Step 3: Cross multiply
   1,315.09x = 1,815.01 × 866.89
4. Step 4: Simplify right side
   1,315.09x = 1,573,404.94
5. Step 5: Solve for x
   x = 1,573,404.94/1,315.09
6. Step 6: Final answer
   x = 1,196.43