Finding the Fourth Proportional to 82.76, 124.02 and 42.21

Step by Step Solution

1. Step 1: Write the proportion equation
   82.76 : 124.02 = 42.21 : x
2. Step 2: Convert to fraction form
   82.76/124.02 = 42.21/x
3. Step 3: Cross multiply
   82.76x = 124.02 × 42.21
4. Step 4: Simplify right side
   82.76x = 5,234.26
5. Step 5: Solve for x
   x = 5,234.26/82.76
6. Step 6: Final answer
   x = 63.25