Finding the Fourth Proportional to 1,380.92, 1,906.32 and 884.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.92 : 1,906.32 = 884.28 : x
2. Step 2: Convert to fraction form
   1,380.92/1,906.32 = 884.28/x
3. Step 3: Cross multiply
   1,380.92x = 1,906.32 × 884.28
4. Step 4: Simplify right side
   1,380.92x = 1,685,720.65
5. Step 5: Solve for x
   x = 1,685,720.65/1,380.92
6. Step 6: Final answer
   x = 1,220.72