Finding the Fourth Proportional to 1,388.52, 1,915.50 and 947.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.52 : 1,915.50 = 947.04 : x
2. Step 2: Convert to fraction form
   1,388.52/1,915.50 = 947.04/x
3. Step 3: Cross multiply
   1,388.52x = 1,915.50 × 947.04
4. Step 4: Simplify right side
   1,388.52x = 1,814,055.12
5. Step 5: Solve for x
   x = 1,814,055.12/1,388.52
6. Step 6: Final answer
   x = 1,306.47