Finding the Fourth Proportional to 1,340.25, 1,849.80 and 780.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,340.25 : 1,849.80 = 780.84 : x
2. Step 2: Convert to fraction form
   1,340.25/1,849.80 = 780.84/x
3. Step 3: Cross multiply
   1,340.25x = 1,849.80 × 780.84
4. Step 4: Simplify right side
   1,340.25x = 1,444,397.83
5. Step 5: Solve for x
   x = 1,444,397.83/1,340.25
6. Step 6: Final answer
   x = 1,077.71