Finding the Fourth Proportional to 1,152.87, 1,590.96 and 628.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,152.87 : 1,590.96 = 628.89 : x
2. Step 2: Convert to fraction form
   1,152.87/1,590.96 = 628.89/x
3. Step 3: Cross multiply
   1,152.87x = 1,590.96 × 628.89
4. Step 4: Simplify right side
   1,152.87x = 1,000,538.83
5. Step 5: Solve for x
   x = 1,000,538.83/1,152.87
6. Step 6: Final answer
   x = 867.87