Finding the Fourth Proportional to 1,438.56, 1,986.12 and 996.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,438.56 : 1,986.12 = 996.30 : x
2. Step 2: Convert to fraction form
   1,438.56/1,986.12 = 996.30/x
3. Step 3: Cross multiply
   1,438.56x = 1,986.12 × 996.30
4. Step 4: Simplify right side
   1,438.56x = 1,978,771.36
5. Step 5: Solve for x
   x = 1,978,771.36/1,438.56
6. Step 6: Final answer
   x = 1,375.52