Finding the Third Proportional to 40.31 and 56.72

Step by Step Solution

1. Step 1: Write the proportion equation
   40.31 : 56.72 = 56.72 : x
2. Step 2: Convert to fraction form
   40.31/56.72 = 56.72/x
3. Step 3: Cross multiply
   40.31x = 56.72 × 56.72
4. Step 4: Simplify right side
   40.31x = 3,217.02
5. Step 5: Solve for x
   x = 3,217.02/40.31
6. Step 6: Final answer
   x = 79.80