Finding the Fourth Proportional to 82.63, 123.99 and 42.09

Step by Step Solution

1. Step 1: Write the proportion equation
   82.63 : 123.99 = 42.09 : x
2. Step 2: Convert to fraction form
   82.63/123.99 = 42.09/x
3. Step 3: Cross multiply
   82.63x = 123.99 × 42.09
4. Step 4: Simplify right side
   82.63x = 5,218.74
5. Step 5: Solve for x
   x = 5,218.74/82.63
6. Step 6: Final answer
   x = 63.16