Finding the Fourth Proportional to 67.22, 100.72 and 42.79

Step by Step Solution

1. Step 1: Write the proportion equation
   67.22 : 100.72 = 42.79 : x
2. Step 2: Convert to fraction form
   67.22/100.72 = 42.79/x
3. Step 3: Cross multiply
   67.22x = 100.72 × 42.79
4. Step 4: Simplify right side
   67.22x = 4,309.81
5. Step 5: Solve for x
   x = 4,309.81/67.22
6. Step 6: Final answer
   x = 64.11