Finding the Third Proportional to 78,991 and 175,478

Step by Step Solution

1. Step 1: Write the proportion equation
   78,991 : 175,478 = 175,478 : x
2. Step 2: Convert to fraction form
   78,991/175,478 = 175,478/x
3. Step 3: Cross multiply
   78,991x = 175,478 × 175,478
4. Step 4: Simplify right side
   78,991x = 30,792,528,484
5. Step 5: Solve for x
   x = 30,792,528,484/78,991
6. Step 6: Final answer
   x = 389,823.25