Finding the Fourth Proportional to 1,401.72, 1,934.28 and 812.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,401.72 : 1,934.28 = 812.16 : x
2. Step 2: Convert to fraction form
   1,401.72/1,934.28 = 812.16/x
3. Step 3: Cross multiply
   1,401.72x = 1,934.28 × 812.16
4. Step 4: Simplify right side
   1,401.72x = 1,570,944.84
5. Step 5: Solve for x
   x = 1,570,944.84/1,401.72
6. Step 6: Final answer
   x = 1,120.73