Finding the Fourth Proportional to 2,085.48, 3,128.40 and 624.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.48 : 3,128.40 = 624.78 : x
2. Step 2: Convert to fraction form
   2,085.48/3,128.40 = 624.78/x
3. Step 3: Cross multiply
   2,085.48x = 3,128.40 × 624.78
4. Step 4: Simplify right side
   2,085.48x = 1,954,561.75
5. Step 5: Solve for x
   x = 1,954,561.75/2,085.48
6. Step 6: Final answer
   x = 937.22