Finding the Third Proportional to 143,808.75 and 309,690

Step by Step Solution

1. Step 1: Write the proportion equation
   143,808.75 : 309,690 = 309,690 : x
2. Step 2: Convert to fraction form
   143,808.75/309,690 = 309,690/x
3. Step 3: Cross multiply
   143,808.75x = 309,690 × 309,690
4. Step 4: Simplify right side
   143,808.75x = 95,907,896,100
5. Step 5: Solve for x
   x = 95,907,896,100/143,808.75
6. Step 6: Final answer
   x = 666,912.80