Finding the Fourth Proportional to 1,066.71, 1,471.73 and 717.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,066.71 : 1,471.73 = 717.60 : x
2. Step 2: Convert to fraction form
   1,066.71/1,471.73 = 717.60/x
3. Step 3: Cross multiply
   1,066.71x = 1,471.73 × 717.60
4. Step 4: Simplify right side
   1,066.71x = 1,056,109.86
5. Step 5: Solve for x
   x = 1,056,109.86/1,066.71
6. Step 6: Final answer
   x = 990.06