Finding the Fourth Proportional to 1,388.39, 1,915.98 and 767.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.39 : 1,915.98 = 767.39 : x
2. Step 2: Convert to fraction form
   1,388.39/1,915.98 = 767.39/x
3. Step 3: Cross multiply
   1,388.39x = 1,915.98 × 767.39
4. Step 4: Simplify right side
   1,388.39x = 1,470,303.89
5. Step 5: Solve for x
   x = 1,470,303.89/1,388.39
6. Step 6: Final answer
   x = 1,059.00