Finding the Fourth Proportional to 1,386.41, 1,913.27 and 788.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.41 : 1,913.27 = 788.99 : x
2. Step 2: Convert to fraction form
   1,386.41/1,913.27 = 788.99/x
3. Step 3: Cross multiply
   1,386.41x = 1,913.27 × 788.99
4. Step 4: Simplify right side
   1,386.41x = 1,509,537.39
5. Step 5: Solve for x
   x = 1,509,537.39/1,386.41
6. Step 6: Final answer
   x = 1,088.81