Finding the Fourth Proportional to 1,820.48, 2,731.59 and 780.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,820.48 : 2,731.59 = 780.84 : x
2. Step 2: Convert to fraction form
   1,820.48/2,731.59 = 780.84/x
3. Step 3: Cross multiply
   1,820.48x = 2,731.59 × 780.84
4. Step 4: Simplify right side
   1,820.48x = 2,132,934.74
5. Step 5: Solve for x
   x = 2,132,934.74/1,820.48
6. Step 6: Final answer
   x = 1,171.64