Finding the Fourth Proportional to 82.56, 123.83 and 21.70

Step by Step Solution

1. Step 1: Write the proportion equation
   82.56 : 123.83 = 21.70 : x
2. Step 2: Convert to fraction form
   82.56/123.83 = 21.70/x
3. Step 3: Cross multiply
   82.56x = 123.83 × 21.70
4. Step 4: Simplify right side
   82.56x = 2,686.49
5. Step 5: Solve for x
   x = 2,686.49/82.56
6. Step 6: Final answer
   x = 32.54