Finding the Fourth Proportional to 1,340.24, 1,849.72 and 780.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,340.24 : 1,849.72 = 780.89 : x
2. Step 2: Convert to fraction form
   1,340.24/1,849.72 = 780.89/x
3. Step 3: Cross multiply
   1,340.24x = 1,849.72 × 780.89
4. Step 4: Simplify right side
   1,340.24x = 1,444,417.42
5. Step 5: Solve for x
   x = 1,444,417.42/1,340.24
6. Step 6: Final answer
   x = 1,077.73