Finding the Fourth Proportional to 82.29, 123.42 and 21.42

Step by Step Solution

1. Step 1: Write the proportion equation
   82.29 : 123.42 = 21.42 : x
2. Step 2: Convert to fraction form
   82.29/123.42 = 21.42/x
3. Step 3: Cross multiply
   82.29x = 123.42 × 21.42
4. Step 4: Simplify right side
   82.29x = 2,643.66
5. Step 5: Solve for x
   x = 2,643.66/82.29
6. Step 6: Final answer
   x = 32.13