Finding the Third Proportional to 89,309 and 121,290

Step by Step Solution

1. Step 1: Write the proportion equation
   89,309 : 121,290 = 121,290 : x
2. Step 2: Convert to fraction form
   89,309/121,290 = 121,290/x
3. Step 3: Cross multiply
   89,309x = 121,290 × 121,290
4. Step 4: Simplify right side
   89,309x = 14,711,264,100
5. Step 5: Solve for x
   x = 14,711,264,100/89,309
6. Step 6: Final answer
   x = 164,723.20