Finding the Third Proportional to 66,217.50 and 99,599.63

Step by Step Solution

1. Step 1: Write the proportion equation
   66,217.50 : 99,599.63 = 99,599.63 : x
2. Step 2: Convert to fraction form
   66,217.50/99,599.63 = 99,599.63/x
3. Step 3: Cross multiply
   66,217.50x = 99,599.63 × 99,599.63
4. Step 4: Simplify right side
   66,217.50x = 9,920,085,300.14
5. Step 5: Solve for x
   x = 9,920,085,300.14/66,217.50
6. Step 6: Final answer
   x = 149,810.63