Finding the Fourth Proportional to 1,528.15, 2,108.78 and 865.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,528.15 : 2,108.78 = 865.04 : x
2. Step 2: Convert to fraction form
   1,528.15/2,108.78 = 865.04/x
3. Step 3: Cross multiply
   1,528.15x = 2,108.78 × 865.04
4. Step 4: Simplify right side
   1,528.15x = 1,824,173.78
5. Step 5: Solve for x
   x = 1,824,173.78/1,528.15
6. Step 6: Final answer
   x = 1,193.72