Finding the Third Proportional to 77,980 and 111,515

Step by Step Solution

1. Step 1: Write the proportion equation
   77,980 : 111,515 = 111,515 : x
2. Step 2: Convert to fraction form
   77,980/111,515 = 111,515/x
3. Step 3: Cross multiply
   77,980x = 111,515 × 111,515
4. Step 4: Simplify right side
   77,980x = 12,435,595,225
5. Step 5: Solve for x
   x = 12,435,595,225/77,980
6. Step 6: Final answer
   x = 159,471.60