Finding the Fourth Proportional to 100.55, 150.82 and 80.50

Step by Step Solution

1. Step 1: Write the proportion equation
   100.55 : 150.82 = 80.50 : x
2. Step 2: Convert to fraction form
   100.55/150.82 = 80.50/x
3. Step 3: Cross multiply
   100.55x = 150.82 × 80.50
4. Step 4: Simplify right side
   100.55x = 12,140.23
5. Step 5: Solve for x
   x = 12,140.23/100.55
6. Step 6: Final answer
   x = 120.74