Finding the Fourth Proportional to 1,018.36, 1,526.78 and 505.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,018.36 : 1,526.78 = 505.72 : x
2. Step 2: Convert to fraction form
   1,018.36/1,526.78 = 505.72/x
3. Step 3: Cross multiply
   1,018.36x = 1,526.78 × 505.72
4. Step 4: Simplify right side
   1,018.36x = 772,123.18
5. Step 5: Solve for x
   x = 772,123.18/1,018.36
6. Step 6: Final answer
   x = 758.20