Finding the Fourth Proportional to 1,389.30, 1,915.74 and 946.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.30 : 1,915.74 = 946.32 : x
2. Step 2: Convert to fraction form
   1,389.30/1,915.74 = 946.32/x
3. Step 3: Cross multiply
   1,389.30x = 1,915.74 × 946.32
4. Step 4: Simplify right side
   1,389.30x = 1,812,903.08
5. Step 5: Solve for x
   x = 1,812,903.08/1,389.30
6. Step 6: Final answer
   x = 1,304.90