Finding the Fourth Proportional to 1,821.32, 2,731.55 and 780.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,821.32 : 2,731.55 = 780.83 : x
2. Step 2: Convert to fraction form
   1,821.32/2,731.55 = 780.83/x
3. Step 3: Cross multiply
   1,821.32x = 2,731.55 × 780.83
4. Step 4: Simplify right side
   1,821.32x = 2,132,858.62
5. Step 5: Solve for x
   x = 2,132,858.62/1,821.32
6. Step 6: Final answer
   x = 1,171.05