Finding the Fourth Proportional to 1,087.53, 1,500.77 and 621.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,087.53 : 1,500.77 = 621.75 : x
2. Step 2: Convert to fraction form
   1,087.53/1,500.77 = 621.75/x
3. Step 3: Cross multiply
   1,087.53x = 1,500.77 × 621.75
4. Step 4: Simplify right side
   1,087.53x = 933,100.64
5. Step 5: Solve for x
   x = 933,100.64/1,087.53
6. Step 6: Final answer
   x = 858.00