Finding the Fourth Proportional to 2,572.42, 3,857.16 and 817.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,572.42 : 3,857.16 = 817.09 : x
2. Step 2: Convert to fraction form
   2,572.42/3,857.16 = 817.09/x
3. Step 3: Cross multiply
   2,572.42x = 3,857.16 × 817.09
4. Step 4: Simplify right side
   2,572.42x = 3,151,646.86
5. Step 5: Solve for x
   x = 3,151,646.86/2,572.42
6. Step 6: Final answer
   x = 1,225.17