Finding the Fourth Proportional to 100.39, 150.71 and 71.68

Step by Step Solution

1. Step 1: Write the proportion equation
   100.39 : 150.71 = 71.68 : x
2. Step 2: Convert to fraction form
   100.39/150.71 = 71.68/x
3. Step 3: Cross multiply
   100.39x = 150.71 × 71.68
4. Step 4: Simplify right side
   100.39x = 10,802.89
5. Step 5: Solve for x
   x = 10,802.89/100.39
6. Step 6: Final answer
   x = 107.61