Finding the Third Proportional to 188,507 and 390,136

Step by Step Solution

1. Step 1: Write the proportion equation
   188,507 : 390,136 = 390,136 : x
2. Step 2: Convert to fraction form
   188,507/390,136 = 390,136/x
3. Step 3: Cross multiply
   188,507x = 390,136 × 390,136
4. Step 4: Simplify right side
   188,507x = 152,206,098,496
5. Step 5: Solve for x
   x = 152,206,098,496/188,507
6. Step 6: Final answer
   x = 807,429.42