Finding the Fourth Proportional to 1,090.50, 1,504.88 and 648.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,090.50 : 1,504.88 = 648.39 : x
2. Step 2: Convert to fraction form
   1,090.50/1,504.88 = 648.39/x
3. Step 3: Cross multiply
   1,090.50x = 1,504.88 × 648.39
4. Step 4: Simplify right side
   1,090.50x = 975,751.86
5. Step 5: Solve for x
   x = 975,751.86/1,090.50
6. Step 6: Final answer
   x = 894.77