Finding the Fourth Proportional to 1,818.42, 2,509.32 and 990.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,818.42 : 2,509.32 = 990.42 : x
2. Step 2: Convert to fraction form
   1,818.42/2,509.32 = 990.42/x
3. Step 3: Cross multiply
   1,818.42x = 2,509.32 × 990.42
4. Step 4: Simplify right side
   1,818.42x = 2,485,280.71
5. Step 5: Solve for x
   x = 2,485,280.71/1,818.42
6. Step 6: Final answer
   x = 1,366.73