Finding the Fourth Proportional to 1,086.99, 1,500.24 and 621.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.99 : 1,500.24 = 621.24 : x
2. Step 2: Convert to fraction form
   1,086.99/1,500.24 = 621.24/x
3. Step 3: Cross multiply
   1,086.99x = 1,500.24 × 621.24
4. Step 4: Simplify right side
   1,086.99x = 932,009.10
5. Step 5: Solve for x
   x = 932,009.10/1,086.99
6. Step 6: Final answer
   x = 857.42