Finding the Third Proportional to 78,400 and 117,776.50

Step by Step Solution

1. Step 1: Write the proportion equation
   78,400 : 117,776.50 = 117,776.50 : x
2. Step 2: Convert to fraction form
   78,400/117,776.50 = 117,776.50/x
3. Step 3: Cross multiply
   78,400x = 117,776.50 × 117,776.50
4. Step 4: Simplify right side
   78,400x = 13,871,303,952.25
5. Step 5: Solve for x
   x = 13,871,303,952.25/78,400
6. Step 6: Final answer
   x = 176,929.90