Finding the Third Proportional to 42,407 and 72,216.50

Step by Step Solution

1. Step 1: Write the proportion equation
   42,407 : 72,216.50 = 72,216.50 : x
2. Step 2: Convert to fraction form
   42,407/72,216.50 = 72,216.50/x
3. Step 3: Cross multiply
   42,407x = 72,216.50 × 72,216.50
4. Step 4: Simplify right side
   42,407x = 5,215,222,872.25
5. Step 5: Solve for x
   x = 5,215,222,872.25/42,407
6. Step 6: Final answer
   x = 122,980.24