Finding the Fourth Proportional to 1,107.39, 1,527.72 and 812.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,107.39 : 1,527.72 = 812.15 : x
2. Step 2: Convert to fraction form
   1,107.39/1,527.72 = 812.15/x
3. Step 3: Cross multiply
   1,107.39x = 1,527.72 × 812.15
4. Step 4: Simplify right side
   1,107.39x = 1,240,730.16
5. Step 5: Solve for x
   x = 1,240,730.16/1,107.39
6. Step 6: Final answer
   x = 1,120.41