Finding the Fourth Proportional to 1,005.15, 1,506.69 and 571.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.15 : 1,506.69 = 571.38 : x
2. Step 2: Convert to fraction form
   1,005.15/1,506.69 = 571.38/x
3. Step 3: Cross multiply
   1,005.15x = 1,506.69 × 571.38
4. Step 4: Simplify right side
   1,005.15x = 860,892.53
5. Step 5: Solve for x
   x = 860,892.53/1,005.15
6. Step 6: Final answer
   x = 856.48