Finding the Fourth Proportional to 1,591.28, 2,385.76 and 768.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,591.28 : 2,385.76 = 768.76 : x
2. Step 2: Convert to fraction form
   1,591.28/2,385.76 = 768.76/x
3. Step 3: Cross multiply
   1,591.28x = 2,385.76 × 768.76
4. Step 4: Simplify right side
   1,591.28x = 1,834,076.86
5. Step 5: Solve for x
   x = 1,834,076.86/1,591.28
6. Step 6: Final answer
   x = 1,152.58