Finding the Fourth Proportional to 1,384.39, 1,907.83 and 990.73

Step by Step Solution

1. Step 1: Write the proportion equation
   1,384.39 : 1,907.83 = 990.73 : x
2. Step 2: Convert to fraction form
   1,384.39/1,907.83 = 990.73/x
3. Step 3: Cross multiply
   1,384.39x = 1,907.83 × 990.73
4. Step 4: Simplify right side
   1,384.39x = 1,890,144.42
5. Step 5: Solve for x
   x = 1,890,144.42/1,384.39
6. Step 6: Final answer
   x = 1,365.33