Finding the Third Proportional to 78,485 and 111,807.50

Step by Step Solution

1. Step 1: Write the proportion equation
   78,485 : 111,807.50 = 111,807.50 : x
2. Step 2: Convert to fraction form
   78,485/111,807.50 = 111,807.50/x
3. Step 3: Cross multiply
   78,485x = 111,807.50 × 111,807.50
4. Step 4: Simplify right side
   78,485x = 12,500,917,056.25
5. Step 5: Solve for x
   x = 12,500,917,056.25/78,485
6. Step 6: Final answer
   x = 159,277.79