Finding the Third Proportional to 20,138 and 42,178

Step by Step Solution

1. Step 1: Write the proportion equation
   20,138 : 42,178 = 42,178 : x
2. Step 2: Convert to fraction form
   20,138/42,178 = 42,178/x
3. Step 3: Cross multiply
   20,138x = 42,178 × 42,178
4. Step 4: Simplify right side
   20,138x = 1,778,983,684
5. Step 5: Solve for x
   x = 1,778,983,684/20,138
6. Step 6: Final answer
   x = 88,339.64