Finding the Fourth Proportional to 82.42, 123.31 and 48.21

Step by Step Solution

1. Step 1: Write the proportion equation
   82.42 : 123.31 = 48.21 : x
2. Step 2: Convert to fraction form
   82.42/123.31 = 48.21/x
3. Step 3: Cross multiply
   82.42x = 123.31 × 48.21
4. Step 4: Simplify right side
   82.42x = 5,944.78
5. Step 5: Solve for x
   x = 5,944.78/82.42
6. Step 6: Final answer
   x = 72.13