Finding the Fourth Proportional to 1,391.43, 1,920.17 and 761.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,391.43 : 1,920.17 = 761.96 : x
2. Step 2: Convert to fraction form
   1,391.43/1,920.17 = 761.96/x
3. Step 3: Cross multiply
   1,391.43x = 1,920.17 × 761.96
4. Step 4: Simplify right side
   1,391.43x = 1,463,082.18
5. Step 5: Solve for x
   x = 1,463,082.18/1,391.43
6. Step 6: Final answer
   x = 1,051.50