Finding the Fourth Proportional to 1,388.07, 1,915.52 and 767.07

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.07 : 1,915.52 = 767.07 : x
2. Step 2: Convert to fraction form
   1,388.07/1,915.52 = 767.07/x
3. Step 3: Cross multiply
   1,388.07x = 1,915.52 × 767.07
4. Step 4: Simplify right side
   1,388.07x = 1,469,337.93
5. Step 5: Solve for x
   x = 1,469,337.93/1,388.07
6. Step 6: Final answer
   x = 1,058.55