Finding the Fourth Proportional to 1,090.91, 1,505.39 and 618.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,090.91 : 1,505.39 = 618.82 : x
2. Step 2: Convert to fraction form
   1,090.91/1,505.39 = 618.82/x
3. Step 3: Cross multiply
   1,090.91x = 1,505.39 × 618.82
4. Step 4: Simplify right side
   1,090.91x = 931,563.22
5. Step 5: Solve for x
   x = 931,563.22/1,090.91
6. Step 6: Final answer
   x = 853.94