Finding the Fourth Proportional to 109.78, 164.71 and 71.33

Step by Step Solution

1. Step 1: Write the proportion equation
   109.78 : 164.71 = 71.33 : x
2. Step 2: Convert to fraction form
   109.78/164.71 = 71.33/x
3. Step 3: Cross multiply
   109.78x = 164.71 × 71.33
4. Step 4: Simplify right side
   109.78x = 11,749.00
5. Step 5: Solve for x
   x = 11,749.00/109.78
6. Step 6: Final answer
   x = 107.03