Finding the Fourth Proportional to 1,066.40, 1,470.78 and 693.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,066.40 : 1,470.78 = 693.50 : x
2. Step 2: Convert to fraction form
   1,066.40/1,470.78 = 693.50/x
3. Step 3: Cross multiply
   1,066.40x = 1,470.78 × 693.50
4. Step 4: Simplify right side
   1,066.40x = 1,019,978.58
5. Step 5: Solve for x
   x = 1,019,978.58/1,066.40
6. Step 6: Final answer
   x = 956.47