Finding the Fourth Proportional to 1,443.65, 1,992.24 and 780.51

Step by Step Solution

1. Step 1: Write the proportion equation
   1,443.65 : 1,992.24 = 780.51 : x
2. Step 2: Convert to fraction form
   1,443.65/1,992.24 = 780.51/x
3. Step 3: Cross multiply
   1,443.65x = 1,992.24 × 780.51
4. Step 4: Simplify right side
   1,443.65x = 1,554,964.22
5. Step 5: Solve for x
   x = 1,554,964.22/1,443.65
6. Step 6: Final answer
   x = 1,077.10