Finding the Fourth Proportional to 1,224.24, 1,689.72 and 775.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,224.24 : 1,689.72 = 775.82 : x
2. Step 2: Convert to fraction form
   1,224.24/1,689.72 = 775.82/x
3. Step 3: Cross multiply
   1,224.24x = 1,689.72 × 775.82
4. Step 4: Simplify right side
   1,224.24x = 1,310,918.57
5. Step 5: Solve for x
   x = 1,310,918.57/1,224.24
6. Step 6: Final answer
   x = 1,070.80