Finding the Fourth Proportional to 1,215.48, 1,824.10 and 485.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,215.48 : 1,824.10 = 485.27 : x
2. Step 2: Convert to fraction form
   1,215.48/1,824.10 = 485.27/x
3. Step 3: Cross multiply
   1,215.48x = 1,824.10 × 485.27
4. Step 4: Simplify right side
   1,215.48x = 885,171.89
5. Step 5: Solve for x
   x = 885,171.89/1,215.48
6. Step 6: Final answer
   x = 728.25