Finding the Fourth Proportional to 1,381.85, 2,073.69 and 920.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.85 : 2,073.69 = 920.15 : x
2. Step 2: Convert to fraction form
   1,381.85/2,073.69 = 920.15/x
3. Step 3: Cross multiply
   1,381.85x = 2,073.69 × 920.15
4. Step 4: Simplify right side
   1,381.85x = 1,908,105.85
5. Step 5: Solve for x
   x = 1,908,105.85/1,381.85
6. Step 6: Final answer
   x = 1,380.83