Finding the Fourth Proportional to 2,588.72, 3,883.26 and 858.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,588.72 : 3,883.26 = 858.56 : x
2. Step 2: Convert to fraction form
   2,588.72/3,883.26 = 858.56/x
3. Step 3: Cross multiply
   2,588.72x = 3,883.26 × 858.56
4. Step 4: Simplify right side
   2,588.72x = 3,334,011.71
5. Step 5: Solve for x
   x = 3,334,011.71/2,588.72
6. Step 6: Final answer
   x = 1,287.90