Finding the Fourth Proportional to 1,438.30, 1,984.32 and 878.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,438.30 : 1,984.32 = 878.38 : x
2. Step 2: Convert to fraction form
   1,438.30/1,984.32 = 878.38/x
3. Step 3: Cross multiply
   1,438.30x = 1,984.32 × 878.38
4. Step 4: Simplify right side
   1,438.30x = 1,742,987.00
5. Step 5: Solve for x
   x = 1,742,987.00/1,438.30
6. Step 6: Final answer
   x = 1,211.84