Finding the Fourth Proportional to 1,401.86, 1,934.21 and 812.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,401.86 : 1,934.21 = 812.05 : x
2. Step 2: Convert to fraction form
   1,401.86/1,934.21 = 812.05/x
3. Step 3: Cross multiply
   1,401.86x = 1,934.21 × 812.05
4. Step 4: Simplify right side
   1,401.86x = 1,570,672.43
5. Step 5: Solve for x
   x = 1,570,672.43/1,401.86
6. Step 6: Final answer
   x = 1,120.42