Finding the Fourth Proportional to 71.72, 107.06 and 67.43

Step by Step Solution

1. Step 1: Write the proportion equation
   71.72 : 107.06 = 67.43 : x
2. Step 2: Convert to fraction form
   71.72/107.06 = 67.43/x
3. Step 3: Cross multiply
   71.72x = 107.06 × 67.43
4. Step 4: Simplify right side
   71.72x = 7,218.18
5. Step 5: Solve for x
   x = 7,218.18/71.72
6. Step 6: Final answer
   x = 100.65