Finding the Third Proportional to 35,739 and 78,390

Step by Step Solution

1. Step 1: Write the proportion equation
   35,739 : 78,390 = 78,390 : x
2. Step 2: Convert to fraction form
   35,739/78,390 = 78,390/x
3. Step 3: Cross multiply
   35,739x = 78,390 × 78,390
4. Step 4: Simplify right side
   35,739x = 6,144,992,100
5. Step 5: Solve for x
   x = 6,144,992,100/35,739
6. Step 6: Final answer
   x = 171,940.80