Finding the Fourth Proportional to 1,443.01, 1,991.35 and 779.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,443.01 : 1,991.35 = 779.86 : x
2. Step 2: Convert to fraction form
   1,443.01/1,991.35 = 779.86/x
3. Step 3: Cross multiply
   1,443.01x = 1,991.35 × 779.86
4. Step 4: Simplify right side
   1,443.01x = 1,552,974.21
5. Step 5: Solve for x
   x = 1,552,974.21/1,443.01
6. Step 6: Final answer
   x = 1,076.20