Finding the Fourth Proportional to 1,304.79, 1,800.72 and 780.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,304.79 : 1,800.72 = 780.99 : x
2. Step 2: Convert to fraction form
   1,304.79/1,800.72 = 780.99/x
3. Step 3: Cross multiply
   1,304.79x = 1,800.72 × 780.99
4. Step 4: Simplify right side
   1,304.79x = 1,406,344.31
5. Step 5: Solve for x
   x = 1,406,344.31/1,304.79
6. Step 6: Final answer
   x = 1,077.83