Finding the Fourth Proportional to 1,528.55, 2,288.72 and 1,257.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,528.55 : 2,288.72 = 1,257.91 : x
2. Step 2: Convert to fraction form
   1,528.55/2,288.72 = 1,257.91/x
3. Step 3: Cross multiply
   1,528.55x = 2,288.72 × 1,257.91
4. Step 4: Simplify right side
   1,528.55x = 2,879,003.78
5. Step 5: Solve for x
   x = 2,879,003.78/1,528.55
6. Step 6: Final answer
   x = 1,883.49