Finding the Third Proportional to 31,603 and 72,978

Step by Step Solution

1. Step 1: Write the proportion equation
   31,603 : 72,978 = 72,978 : x
2. Step 2: Convert to fraction form
   31,603/72,978 = 72,978/x
3. Step 3: Cross multiply
   31,603x = 72,978 × 72,978
4. Step 4: Simplify right side
   31,603x = 5,325,788,484
5. Step 5: Solve for x
   x = 5,325,788,484/31,603
6. Step 6: Final answer
   x = 168,521.61