Finding the Fourth Proportional to 1,724.56, 2,380.61 and 1,165.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,724.56 : 2,380.61 = 1,165.78 : x
2. Step 2: Convert to fraction form
   1,724.56/2,380.61 = 1,165.78/x
3. Step 3: Cross multiply
   1,724.56x = 2,380.61 × 1,165.78
4. Step 4: Simplify right side
   1,724.56x = 2,775,273.42
5. Step 5: Solve for x
   x = 2,775,273.42/1,724.56
6. Step 6: Final answer
   x = 1,609.27