Finding the Fourth Proportional to 1,621.72, 2,431.42 and 755.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,621.72 : 2,431.42 = 755.56 : x
2. Step 2: Convert to fraction form
   1,621.72/2,431.42 = 755.56/x
3. Step 3: Cross multiply
   1,621.72x = 2,431.42 × 755.56
4. Step 4: Simplify right side
   1,621.72x = 1,837,083.70
5. Step 5: Solve for x
   x = 1,837,083.70/1,621.72
6. Step 6: Final answer
   x = 1,132.80