Finding the Third Proportional to 42.40 and 90.49

Step by Step Solution

1. Step 1: Write the proportion equation
   42.40 : 90.49 = 90.49 : x
2. Step 2: Convert to fraction form
   42.40/90.49 = 90.49/x
3. Step 3: Cross multiply
   42.40x = 90.49 × 90.49
4. Step 4: Simplify right side
   42.40x = 8,188.84
5. Step 5: Solve for x
   x = 8,188.84/42.40
6. Step 6: Final answer
   x = 193.14