Finding the Third Proportional to 78,144 and 170,990

Step by Step Solution

1. Step 1: Write the proportion equation
   78,144 : 170,990 = 170,990 : x
2. Step 2: Convert to fraction form
   78,144/170,990 = 170,990/x
3. Step 3: Cross multiply
   78,144x = 170,990 × 170,990
4. Step 4: Simplify right side
   78,144x = 29,237,580,100
5. Step 5: Solve for x
   x = 29,237,580,100/78,144
6. Step 6: Final answer
   x = 374,150.03