Finding the Third Proportional to 85.78 and 188.58

Step by Step Solution

1. Step 1: Write the proportion equation
   85.78 : 188.58 = 188.58 : x
2. Step 2: Convert to fraction form
   85.78/188.58 = 188.58/x
3. Step 3: Cross multiply
   85.78x = 188.58 × 188.58
4. Step 4: Simplify right side
   85.78x = 35,561.71
5. Step 5: Solve for x
   x = 35,561.71/85.78
6. Step 6: Final answer
   x = 414.56