Finding the Fourth Proportional to 1,165.57, 1,608.90 and 772.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,165.57 : 1,608.90 = 772.72 : x
2. Step 2: Convert to fraction form
   1,165.57/1,608.90 = 772.72/x
3. Step 3: Cross multiply
   1,165.57x = 1,608.90 × 772.72
4. Step 4: Simplify right side
   1,165.57x = 1,243,222.29
5. Step 5: Solve for x
   x = 1,243,222.29/1,165.57
6. Step 6: Final answer
   x = 1,066.62