Finding the Fourth Proportional to 1,080.16, 1,490.70 and 607.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,080.16 : 1,490.70 = 607.99 : x
2. Step 2: Convert to fraction form
   1,080.16/1,490.70 = 607.99/x
3. Step 3: Cross multiply
   1,080.16x = 1,490.70 × 607.99
4. Step 4: Simplify right side
   1,080.16x = 906,330.69
5. Step 5: Solve for x
   x = 906,330.69/1,080.16
6. Step 6: Final answer
   x = 839.07