Finding the Fourth Proportional to 1,339.42, 2,009.15 and 880.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,339.42 : 2,009.15 = 880.12 : x
2. Step 2: Convert to fraction form
   1,339.42/2,009.15 = 880.12/x
3. Step 3: Cross multiply
   1,339.42x = 2,009.15 × 880.12
4. Step 4: Simplify right side
   1,339.42x = 1,768,293.10
5. Step 5: Solve for x
   x = 1,768,293.10/1,339.42
6. Step 6: Final answer
   x = 1,320.19