Finding the Fourth Proportional to 82.85, 124.31 and 42.22

Step by Step Solution

1. Step 1: Write the proportion equation
   82.85 : 124.31 = 42.22 : x
2. Step 2: Convert to fraction form
   82.85/124.31 = 42.22/x
3. Step 3: Cross multiply
   82.85x = 124.31 × 42.22
4. Step 4: Simplify right side
   82.85x = 5,248.51
5. Step 5: Solve for x
   x = 5,248.51/82.85
6. Step 6: Final answer
   x = 63.35