Finding the Third Proportional to 43,218 and 58,131

Step by Step Solution

1. Step 1: Write the proportion equation
   43,218 : 58,131 = 58,131 : x
2. Step 2: Convert to fraction form
   43,218/58,131 = 58,131/x
3. Step 3: Cross multiply
   43,218x = 58,131 × 58,131
4. Step 4: Simplify right side
   43,218x = 3,379,213,161
5. Step 5: Solve for x
   x = 3,379,213,161/43,218
6. Step 6: Final answer
   x = 78,189.95