Finding the Third Proportional to 386.86 and 907.45

Step by Step Solution

1. Step 1: Write the proportion equation
   386.86 : 907.45 = 907.45 : x
2. Step 2: Convert to fraction form
   386.86/907.45 = 907.45/x
3. Step 3: Cross multiply
   386.86x = 907.45 × 907.45
4. Step 4: Simplify right side
   386.86x = 823,471.17
5. Step 5: Solve for x
   x = 823,471.17/386.86
6. Step 6: Final answer
   x = 2,128.61