Finding the Fourth Proportional to 1,382.99, 1,907.85 and 823.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,382.99 : 1,907.85 = 823.28 : x
2. Step 2: Convert to fraction form
   1,382.99/1,907.85 = 823.28/x
3. Step 3: Cross multiply
   1,382.99x = 1,907.85 × 823.28
4. Step 4: Simplify right side
   1,382.99x = 1,570,685.21
5. Step 5: Solve for x
   x = 1,570,685.21/1,382.99
6. Step 6: Final answer
   x = 1,135.72