Finding the Fourth Proportional to 1,061.28, 1,591.64 and 412.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.28 : 1,591.64 = 412.48 : x
2. Step 2: Convert to fraction form
   1,061.28/1,591.64 = 412.48/x
3. Step 3: Cross multiply
   1,061.28x = 1,591.64 × 412.48
4. Step 4: Simplify right side
   1,061.28x = 656,519.67
5. Step 5: Solve for x
   x = 656,519.67/1,061.28
6. Step 6: Final answer
   x = 618.61