Finding the Fourth Proportional to 105.59, 144.87 and 100.43

Step by Step Solution

1. Step 1: Write the proportion equation
   105.59 : 144.87 = 100.43 : x
2. Step 2: Convert to fraction form
   105.59/144.87 = 100.43/x
3. Step 3: Cross multiply
   105.59x = 144.87 × 100.43
4. Step 4: Simplify right side
   105.59x = 14,549.29
5. Step 5: Solve for x
   x = 14,549.29/105.59
6. Step 6: Final answer
   x = 137.79