Finding the Third Proportional to 64,990.50 and 139,653

Step by Step Solution

1. Step 1: Write the proportion equation
   64,990.50 : 139,653 = 139,653 : x
2. Step 2: Convert to fraction form
   64,990.50/139,653 = 139,653/x
3. Step 3: Cross multiply
   64,990.50x = 139,653 × 139,653
4. Step 4: Simplify right side
   64,990.50x = 19,502,960,409
5. Step 5: Solve for x
   x = 19,502,960,409/64,990.50
6. Step 6: Final answer
   x = 300,089.40