Finding the Fourth Proportional to 1,339.80, 1,849.81 and 843.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,339.80 : 1,849.81 = 843.20 : x
2. Step 2: Convert to fraction form
   1,339.80/1,849.81 = 843.20/x
3. Step 3: Cross multiply
   1,339.80x = 1,849.81 × 843.20
4. Step 4: Simplify right side
   1,339.80x = 1,559,759.79
5. Step 5: Solve for x
   x = 1,559,759.79/1,339.80
6. Step 6: Final answer
   x = 1,164.17