Finding the Fourth Proportional to 82.05, 123.06 and 56.42

Step by Step Solution

1. Step 1: Write the proportion equation
   82.05 : 123.06 = 56.42 : x
2. Step 2: Convert to fraction form
   82.05/123.06 = 56.42/x
3. Step 3: Cross multiply
   82.05x = 123.06 × 56.42
4. Step 4: Simplify right side
   82.05x = 6,943.05
5. Step 5: Solve for x
   x = 6,943.05/82.05
6. Step 6: Final answer
   x = 84.62