Finding the Fourth Proportional to 1,389.10, 1,915.04 and 946.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.10 : 1,915.04 = 946.24 : x
2. Step 2: Convert to fraction form
   1,389.10/1,915.04 = 946.24/x
3. Step 3: Cross multiply
   1,389.10x = 1,915.04 × 946.24
4. Step 4: Simplify right side
   1,389.10x = 1,812,087.45
5. Step 5: Solve for x
   x = 1,812,087.45/1,389.10
6. Step 6: Final answer
   x = 1,304.50