Finding the Fourth Proportional to 1,065.72, 1,597.68 and 407.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,065.72 : 1,597.68 = 407.40 : x
2. Step 2: Convert to fraction form
   1,065.72/1,597.68 = 407.40/x
3. Step 3: Cross multiply
   1,065.72x = 1,597.68 × 407.40
4. Step 4: Simplify right side
   1,065.72x = 650,894.83
5. Step 5: Solve for x
   x = 650,894.83/1,065.72
6. Step 6: Final answer
   x = 610.76