Finding the Fourth Proportional to 1,007.17, 1,389.57 and 564.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.17 : 1,389.57 = 564.99 : x
2. Step 2: Convert to fraction form
   1,007.17/1,389.57 = 564.99/x
3. Step 3: Cross multiply
   1,007.17x = 1,389.57 × 564.99
4. Step 4: Simplify right side
   1,007.17x = 785,085.82
5. Step 5: Solve for x
   x = 785,085.82/1,007.17
6. Step 6: Final answer
   x = 779.50