Finding the Fourth Proportional to 1,078.56, 1,487.84 and 630.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,078.56 : 1,487.84 = 630.50 : x
2. Step 2: Convert to fraction form
   1,078.56/1,487.84 = 630.50/x
3. Step 3: Cross multiply
   1,078.56x = 1,487.84 × 630.50
4. Step 4: Simplify right side
   1,078.56x = 938,072.53
5. Step 5: Solve for x
   x = 938,072.53/1,078.56
6. Step 6: Final answer
   x = 869.75