Finding the Fourth Proportional to 1,420.96, 1,960.77 and 831.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,420.96 : 1,960.77 = 831.46 : x
2. Step 2: Convert to fraction form
   1,420.96/1,960.77 = 831.46/x
3. Step 3: Cross multiply
   1,420.96x = 1,960.77 × 831.46
4. Step 4: Simplify right side
   1,420.96x = 1,630,301.82
5. Step 5: Solve for x
   x = 1,630,301.82/1,420.96
6. Step 6: Final answer
   x = 1,147.32