Finding the Fourth Proportional to 1,008.67, 1,391.71 and 772.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,008.67 : 1,391.71 = 772.83 : x
2. Step 2: Convert to fraction form
   1,008.67/1,391.71 = 772.83/x
3. Step 3: Cross multiply
   1,008.67x = 1,391.71 × 772.83
4. Step 4: Simplify right side
   1,008.67x = 1,075,555.24
5. Step 5: Solve for x
   x = 1,075,555.24/1,008.67
6. Step 6: Final answer
   x = 1,066.31