Finding the Fourth Proportional to 1,391.59, 1,920.70 and 867.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,391.59 : 1,920.70 = 867.52 : x
2. Step 2: Convert to fraction form
   1,391.59/1,920.70 = 867.52/x
3. Step 3: Cross multiply
   1,391.59x = 1,920.70 × 867.52
4. Step 4: Simplify right side
   1,391.59x = 1,666,240.79
5. Step 5: Solve for x
   x = 1,666,240.79/1,391.59
6. Step 6: Final answer
   x = 1,197.37