Finding the Third Proportional to 18.21 and 42.76

Step by Step Solution

1. Step 1: Write the proportion equation
   18.21 : 42.76 = 42.76 : x
2. Step 2: Convert to fraction form
   18.21/42.76 = 42.76/x
3. Step 3: Cross multiply
   18.21x = 42.76 × 42.76
4. Step 4: Simplify right side
   18.21x = 1,828.06
5. Step 5: Solve for x
   x = 1,828.06/18.21
6. Step 6: Final answer
   x = 100.38