Finding the Fourth Proportional to 67.79, 101.64 and 42.05

Step by Step Solution

1. Step 1: Write the proportion equation
   67.79 : 101.64 = 42.05 : x
2. Step 2: Convert to fraction form
   67.79/101.64 = 42.05/x
3. Step 3: Cross multiply
   67.79x = 101.64 × 42.05
4. Step 4: Simplify right side
   67.79x = 4,273.96
5. Step 5: Solve for x
   x = 4,273.96/67.79
6. Step 6: Final answer
   x = 63.05