Finding the Third Proportional to 81,378 and 123,213

Step by Step Solution

1. Step 1: Write the proportion equation
   81,378 : 123,213 = 123,213 : x
2. Step 2: Convert to fraction form
   81,378/123,213 = 123,213/x
3. Step 3: Cross multiply
   81,378x = 123,213 × 123,213
4. Step 4: Simplify right side
   81,378x = 15,181,443,369
5. Step 5: Solve for x
   x = 15,181,443,369/81,378
6. Step 6: Final answer
   x = 186,554.64