Finding the Fourth Proportional to 1,386.02, 1,912.56 and 765.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,386.02 : 1,912.56 = 765.02 : x
2. Step 2: Convert to fraction form
   1,386.02/1,912.56 = 765.02/x
3. Step 3: Cross multiply
   1,386.02x = 1,912.56 × 765.02
4. Step 4: Simplify right side
   1,386.02x = 1,463,146.65
5. Step 5: Solve for x
   x = 1,463,146.65/1,386.02
6. Step 6: Final answer
   x = 1,055.65