Finding the Fourth Proportional to 1,644.78, 2,467.89 and 720.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,644.78 : 2,467.89 = 720.57 : x
2. Step 2: Convert to fraction form
   1,644.78/2,467.89 = 720.57/x
3. Step 3: Cross multiply
   1,644.78x = 2,467.89 × 720.57
4. Step 4: Simplify right side
   1,644.78x = 1,778,287.50
5. Step 5: Solve for x
   x = 1,778,287.50/1,644.78
6. Step 6: Final answer
   x = 1,081.17