Finding the Third Proportional to 21,989.25 and 42,878.25

Step by Step Solution

1. Step 1: Write the proportion equation
   21,989.25 : 42,878.25 = 42,878.25 : x
2. Step 2: Convert to fraction form
   21,989.25/42,878.25 = 42,878.25/x
3. Step 3: Cross multiply
   21,989.25x = 42,878.25 × 42,878.25
4. Step 4: Simplify right side
   21,989.25x = 1,838,544,323.06
5. Step 5: Solve for x
   x = 1,838,544,323.06/21,989.25
6. Step 6: Final answer
   x = 83,611.05