Finding the Fourth Proportional to 82.72, 124.16 and 42.17

Step by Step Solution

1. Step 1: Write the proportion equation
   82.72 : 124.16 = 42.17 : x
2. Step 2: Convert to fraction form
   82.72/124.16 = 42.17/x
3. Step 3: Cross multiply
   82.72x = 124.16 × 42.17
4. Step 4: Simplify right side
   82.72x = 5,235.81
5. Step 5: Solve for x
   x = 5,235.81/82.72
6. Step 6: Final answer
   x = 63.29