Finding the Third Proportional to 34,420 and 72,978

Step by Step Solution

1. Step 1: Write the proportion equation
   34,420 : 72,978 = 72,978 : x
2. Step 2: Convert to fraction form
   34,420/72,978 = 72,978/x
3. Step 3: Cross multiply
   34,420x = 72,978 × 72,978
4. Step 4: Simplify right side
   34,420x = 5,325,788,484
5. Step 5: Solve for x
   x = 5,325,788,484/34,420
6. Step 6: Final answer
   x = 154,729.47