Finding the Fourth Proportional to 67.21, 100.72 and 43.12

Step by Step Solution

1. Step 1: Write the proportion equation
   67.21 : 100.72 = 43.12 : x
2. Step 2: Convert to fraction form
   67.21/100.72 = 43.12/x
3. Step 3: Cross multiply
   67.21x = 100.72 × 43.12
4. Step 4: Simplify right side
   67.21x = 4,343.05
5. Step 5: Solve for x
   x = 4,343.05/67.21
6. Step 6: Final answer
   x = 64.62