Finding the Fourth Proportional to 1,338.42, 2,005.74 and 989.00

Step by Step Solution

1. Step 1: Write the proportion equation
   1,338.42 : 2,005.74 = 989.00 : x
2. Step 2: Convert to fraction form
   1,338.42/2,005.74 = 989.00/x
3. Step 3: Cross multiply
   1,338.42x = 2,005.74 × 989.00
4. Step 4: Simplify right side
   1,338.42x = 1,983,666.83
5. Step 5: Solve for x
   x = 1,983,666.83/1,338.42
6. Step 6: Final answer
   x = 1,482.10