Finding the Fourth Proportional to 1,131.30, 1,696.42 and 438.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.30 : 1,696.42 = 438.30 : x
2. Step 2: Convert to fraction form
   1,131.30/1,696.42 = 438.30/x
3. Step 3: Cross multiply
   1,131.30x = 1,696.42 × 438.30
4. Step 4: Simplify right side
   1,131.30x = 743,540.89
5. Step 5: Solve for x
   x = 743,540.89/1,131.30
6. Step 6: Final answer
   x = 657.24