Finding the Fourth Proportional to 1,080.27, 1,490.94 and 688.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,080.27 : 1,490.94 = 688.23 : x
2. Step 2: Convert to fraction form
   1,080.27/1,490.94 = 688.23/x
3. Step 3: Cross multiply
   1,080.27x = 1,490.94 × 688.23
4. Step 4: Simplify right side
   1,080.27x = 1,026,109.64
5. Step 5: Solve for x
   x = 1,026,109.64/1,080.27
6. Step 6: Final answer
   x = 949.86