Finding the Fourth Proportional to 1,152.90, 1,591.02 and 680.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,152.90 : 1,591.02 = 680.76 : x
2. Step 2: Convert to fraction form
   1,152.90/1,591.02 = 680.76/x
3. Step 3: Cross multiply
   1,152.90x = 1,591.02 × 680.76
4. Step 4: Simplify right side
   1,152.90x = 1,083,102.78
5. Step 5: Solve for x
   x = 1,083,102.78/1,152.90
6. Step 6: Final answer
   x = 939.46