Finding the Fourth Proportional to 1,086.90, 1,499.63 and 693.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.90 : 1,499.63 = 693.60 : x
2. Step 2: Convert to fraction form
   1,086.90/1,499.63 = 693.60/x
3. Step 3: Cross multiply
   1,086.90x = 1,499.63 × 693.60
4. Step 4: Simplify right side
   1,086.90x = 1,040,139.90
5. Step 5: Solve for x
   x = 1,040,139.90/1,086.90
6. Step 6: Final answer
   x = 956.98