Finding the Fourth Proportional to 1,339.82, 1,848.96 and 780.35

Step by Step Solution

1. Step 1: Write the proportion equation
   1,339.82 : 1,848.96 = 780.35 : x
2. Step 2: Convert to fraction form
   1,339.82/1,848.96 = 780.35/x
3. Step 3: Cross multiply
   1,339.82x = 1,848.96 × 780.35
4. Step 4: Simplify right side
   1,339.82x = 1,442,826.69
5. Step 5: Solve for x
   x = 1,442,826.69/1,339.82
6. Step 6: Final answer
   x = 1,076.89