Finding the Third Proportional to 67,172 and 90,900

Step by Step Solution

1. Step 1: Write the proportion equation
   67,172 : 90,900 = 90,900 : x
2. Step 2: Convert to fraction form
   67,172/90,900 = 90,900/x
3. Step 3: Cross multiply
   67,172x = 90,900 × 90,900
4. Step 4: Simplify right side
   67,172x = 8,262,810,000
5. Step 5: Solve for x
   x = 8,262,810,000/67,172
6. Step 6: Final answer
   x = 123,009.74