Finding the Fourth Proportional to 1,048.59, 1,571.34 and 990.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,048.59 : 1,571.34 = 990.15 : x
2. Step 2: Convert to fraction form
   1,048.59/1,571.34 = 990.15/x
3. Step 3: Cross multiply
   1,048.59x = 1,571.34 × 990.15
4. Step 4: Simplify right side
   1,048.59x = 1,555,862.30
5. Step 5: Solve for x
   x = 1,555,862.30/1,048.59
6. Step 6: Final answer
   x = 1,483.77