Finding the Third Proportional to 66,298.50 and 144,139.50

Step by Step Solution

1. Step 1: Write the proportion equation
   66,298.50 : 144,139.50 = 144,139.50 : x
2. Step 2: Convert to fraction form
   66,298.50/144,139.50 = 144,139.50/x
3. Step 3: Cross multiply
   66,298.50x = 144,139.50 × 144,139.50
4. Step 4: Simplify right side
   66,298.50x = 20,776,195,460.25
5. Step 5: Solve for x
   x = 20,776,195,460.25/66,298.50
6. Step 6: Final answer
   x = 313,373.54