Finding the Third Proportional to 19,881 and 42,138

Step by Step Solution

1. Step 1: Write the proportion equation
   19,881 : 42,138 = 42,138 : x
2. Step 2: Convert to fraction form
   19,881/42,138 = 42,138/x
3. Step 3: Cross multiply
   19,881x = 42,138 × 42,138
4. Step 4: Simplify right side
   19,881x = 1,775,611,044
5. Step 5: Solve for x
   x = 1,775,611,044/19,881
6. Step 6: Final answer
   x = 89,311.96