Finding the Third Proportional to 78.75 and 174.75

Step by Step Solution

1. Step 1: Write the proportion equation
   78.75 : 174.75 = 174.75 : x
2. Step 2: Convert to fraction form
   78.75/174.75 = 174.75/x
3. Step 3: Cross multiply
   78.75x = 174.75 × 174.75
4. Step 4: Simplify right side
   78.75x = 30,537.56
5. Step 5: Solve for x
   x = 30,537.56/78.75
6. Step 6: Final answer
   x = 387.78