Finding the Third Proportional to 65.81 and 142.88

Step by Step Solution

1. Step 1: Write the proportion equation
   65.81 : 142.88 = 142.88 : x
2. Step 2: Convert to fraction form
   65.81/142.88 = 142.88/x
3. Step 3: Cross multiply
   65.81x = 142.88 × 142.88
4. Step 4: Simplify right side
   65.81x = 20,413.27
5. Step 5: Solve for x
   x = 20,413.27/65.81
6. Step 6: Final answer
   x = 310.17