Finding the Fourth Proportional to 105.71, 145.71 and 86.01

Step by Step Solution

1. Step 1: Write the proportion equation
   105.71 : 145.71 = 86.01 : x
2. Step 2: Convert to fraction form
   105.71/145.71 = 86.01/x
3. Step 3: Cross multiply
   105.71x = 145.71 × 86.01
4. Step 4: Simplify right side
   105.71x = 12,532.52
5. Step 5: Solve for x
   x = 12,532.52/105.71
6. Step 6: Final answer
   x = 118.56