Finding the Third Proportional to 42.61 and 72.56

Step by Step Solution

1. Step 1: Write the proportion equation
   42.61 : 72.56 = 72.56 : x
2. Step 2: Convert to fraction form
   42.61/72.56 = 72.56/x
3. Step 3: Cross multiply
   42.61x = 72.56 × 72.56
4. Step 4: Simplify right side
   42.61x = 5,265.32
5. Step 5: Solve for x
   x = 5,265.32/42.61
6. Step 6: Final answer
   x = 123.57