Finding the Fourth Proportional to 100.63, 150.82 and 42.80

Step by Step Solution

1. Step 1: Write the proportion equation
   100.63 : 150.82 = 42.80 : x
2. Step 2: Convert to fraction form
   100.63/150.82 = 42.80/x
3. Step 3: Cross multiply
   100.63x = 150.82 × 42.80
4. Step 4: Simplify right side
   100.63x = 6,455.10
5. Step 5: Solve for x
   x = 6,455.10/100.63
6. Step 6: Final answer
   x = 64.15