Finding the Fourth Proportional to 1,086.50, 1,499.37 and 620.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.50 : 1,499.37 = 620.75 : x
2. Step 2: Convert to fraction form
   1,086.50/1,499.37 = 620.75/x
3. Step 3: Cross multiply
   1,086.50x = 1,499.37 × 620.75
4. Step 4: Simplify right side
   1,086.50x = 930,733.93
5. Step 5: Solve for x
   x = 930,733.93/1,086.50
6. Step 6: Final answer
   x = 856.64