Finding the Fourth Proportional to 1,152.71, 1,727.52 and 421.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,152.71 : 1,727.52 = 421.59 : x
2. Step 2: Convert to fraction form
   1,152.71/1,727.52 = 421.59/x
3. Step 3: Cross multiply
   1,152.71x = 1,727.52 × 421.59
4. Step 4: Simplify right side
   1,152.71x = 728,305.16
5. Step 5: Solve for x
   x = 728,305.16/1,152.71
6. Step 6: Final answer
   x = 631.82