Finding the Fourth Proportional to 1,512.72, 2,086.56 and 1,288.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,512.72 : 2,086.56 = 1,288.08 : x
2. Step 2: Convert to fraction form
   1,512.72/2,086.56 = 1,288.08/x
3. Step 3: Cross multiply
   1,512.72x = 2,086.56 × 1,288.08
4. Step 4: Simplify right side
   1,512.72x = 2,687,656.20
5. Step 5: Solve for x
   x = 2,687,656.20/1,512.72
6. Step 6: Final answer
   x = 1,776.70