Finding the Fourth Proportional to 1,222.22, 1,686.51 and 691.07

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.22 : 1,686.51 = 691.07 : x
2. Step 2: Convert to fraction form
   1,222.22/1,686.51 = 691.07/x
3. Step 3: Cross multiply
   1,222.22x = 1,686.51 × 691.07
4. Step 4: Simplify right side
   1,222.22x = 1,165,488.03
5. Step 5: Solve for x
   x = 1,165,488.03/1,222.22
6. Step 6: Final answer
   x = 953.58