Finding the Fourth Proportional to 1,007.72, 1,510.70 and 520.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.72 : 1,510.70 = 520.52 : x
2. Step 2: Convert to fraction form
   1,007.72/1,510.70 = 520.52/x
3. Step 3: Cross multiply
   1,007.72x = 1,510.70 × 520.52
4. Step 4: Simplify right side
   1,007.72x = 786,349.56
5. Step 5: Solve for x
   x = 786,349.56/1,007.72
6. Step 6: Final answer
   x = 780.33