Finding the Fourth Proportional to 1,389.57, 2,085.27 and 523.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.57 : 2,085.27 = 523.89 : x
2. Step 2: Convert to fraction form
   1,389.57/2,085.27 = 523.89/x
3. Step 3: Cross multiply
   1,389.57x = 2,085.27 × 523.89
4. Step 4: Simplify right side
   1,389.57x = 1,092,452.10
5. Step 5: Solve for x
   x = 1,092,452.10/1,389.57
6. Step 6: Final answer
   x = 786.18