Finding the Fourth Proportional to 42.78, 64.12 and 32.70

Step by Step Solution

1. Step 1: Write the proportion equation
   42.78 : 64.12 = 32.70 : x
2. Step 2: Convert to fraction form
   42.78/64.12 = 32.70/x
3. Step 3: Cross multiply
   42.78x = 64.12 × 32.70
4. Step 4: Simplify right side
   42.78x = 2,096.72
5. Step 5: Solve for x
   x = 2,096.72/42.78
6. Step 6: Final answer
   x = 49.01