Finding the Fourth Proportional to 1,148.40, 1,584.78 and 624.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,148.40 : 1,584.78 = 624.42 : x
2. Step 2: Convert to fraction form
   1,148.40/1,584.78 = 624.42/x
3. Step 3: Cross multiply
   1,148.40x = 1,584.78 × 624.42
4. Step 4: Simplify right side
   1,148.40x = 989,568.33
5. Step 5: Solve for x
   x = 989,568.33/1,148.40
6. Step 6: Final answer
   x = 861.69