Finding the Fourth Proportional to 105.84, 158.58 and 67.20

Step by Step Solution

1. Step 1: Write the proportion equation
   105.84 : 158.58 = 67.20 : x
2. Step 2: Convert to fraction form
   105.84/158.58 = 67.20/x
3. Step 3: Cross multiply
   105.84x = 158.58 × 67.20
4. Step 4: Simplify right side
   105.84x = 10,656.58
5. Step 5: Solve for x
   x = 10,656.58/105.84
6. Step 6: Final answer
   x = 100.69