Finding the Fourth Proportional to 1,049.60, 1,572.72 and 664.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,049.60 : 1,572.72 = 664.08 : x
2. Step 2: Convert to fraction form
   1,049.60/1,572.72 = 664.08/x
3. Step 3: Cross multiply
   1,049.60x = 1,572.72 × 664.08
4. Step 4: Simplify right side
   1,049.60x = 1,044,411.90
5. Step 5: Solve for x
   x = 1,044,411.90/1,049.60
6. Step 6: Final answer
   x = 995.06