Finding the Third Proportional to 77.91 and 170.72

Step by Step Solution

1. Step 1: Write the proportion equation
   77.91 : 170.72 = 170.72 : x
2. Step 2: Convert to fraction form
   77.91/170.72 = 170.72/x
3. Step 3: Cross multiply
   77.91x = 170.72 × 170.72
4. Step 4: Simplify right side
   77.91x = 29,144.89
5. Step 5: Solve for x
   x = 29,144.89/77.91
6. Step 6: Final answer
   x = 374.10