Finding the Fourth Proportional to 143.98, 215.57 and 100.55

Step by Step Solution

1. Step 1: Write the proportion equation
   143.98 : 215.57 = 100.55 : x
2. Step 2: Convert to fraction form
   143.98/215.57 = 100.55/x
3. Step 3: Cross multiply
   143.98x = 215.57 × 100.55
4. Step 4: Simplify right side
   143.98x = 21,676.35
5. Step 5: Solve for x
   x = 21,676.35/143.98
6. Step 6: Final answer
   x = 150.55