Finding the Fourth Proportional to 1,061.84, 1,591.56 and 512.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.84 : 1,591.56 = 512.78 : x
2. Step 2: Convert to fraction form
   1,061.84/1,591.56 = 512.78/x
3. Step 3: Cross multiply
   1,061.84x = 1,591.56 × 512.78
4. Step 4: Simplify right side
   1,061.84x = 816,120.14
5. Step 5: Solve for x
   x = 816,120.14/1,061.84
6. Step 6: Final answer
   x = 768.59