Finding the Fourth Proportional to 1,443.51, 1,992.03 and 780.36

Step by Step Solution

1. Step 1: Write the proportion equation
   1,443.51 : 1,992.03 = 780.36 : x
2. Step 2: Convert to fraction form
   1,443.51/1,992.03 = 780.36/x
3. Step 3: Cross multiply
   1,443.51x = 1,992.03 × 780.36
4. Step 4: Simplify right side
   1,443.51x = 1,554,500.53
5. Step 5: Solve for x
   x = 1,554,500.53/1,443.51
6. Step 6: Final answer
   x = 1,076.89