Finding the Fourth Proportional to 82.72, 124.08 and 42.10

Step by Step Solution

1. Step 1: Write the proportion equation
   82.72 : 124.08 = 42.10 : x
2. Step 2: Convert to fraction form
   82.72/124.08 = 42.10/x
3. Step 3: Cross multiply
   82.72x = 124.08 × 42.10
4. Step 4: Simplify right side
   82.72x = 5,223.77
5. Step 5: Solve for x
   x = 5,223.77/82.72
6. Step 6: Final answer
   x = 63.15