Finding the Fourth Proportional to 2,172.48, 2,998.28 and 1,288.52

Step by Step Solution

1. Step 1: Write the proportion equation
   2,172.48 : 2,998.28 = 1,288.52 : x
2. Step 2: Convert to fraction form
   2,172.48/2,998.28 = 1,288.52/x
3. Step 3: Cross multiply
   2,172.48x = 2,998.28 × 1,288.52
4. Step 4: Simplify right side
   2,172.48x = 3,863,343.75
5. Step 5: Solve for x
   x = 3,863,343.75/2,172.48
6. Step 6: Final answer
   x = 1,778.31