Finding the Fourth Proportional to 1,389.53, 1,917.42 and 822.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.53 : 1,917.42 = 822.59 : x
2. Step 2: Convert to fraction form
   1,389.53/1,917.42 = 822.59/x
3. Step 3: Cross multiply
   1,389.53x = 1,917.42 × 822.59
4. Step 4: Simplify right side
   1,389.53x = 1,577,240.93
5. Step 5: Solve for x
   x = 1,577,240.93/1,389.53
6. Step 6: Final answer
   x = 1,135.09