Finding the Third Proportional to 42,158 and 56,391

Step by Step Solution

1. Step 1: Write the proportion equation
   42,158 : 56,391 = 56,391 : x
2. Step 2: Convert to fraction form
   42,158/56,391 = 56,391/x
3. Step 3: Cross multiply
   42,158x = 56,391 × 56,391
4. Step 4: Simplify right side
   42,158x = 3,179,944,881
5. Step 5: Solve for x
   x = 3,179,944,881/42,158
6. Step 6: Final answer
   x = 75,429.22