Finding the Fourth Proportional to 82.50, 123.72 and 28.36

Step by Step Solution

1. Step 1: Write the proportion equation
   82.50 : 123.72 = 28.36 : x
2. Step 2: Convert to fraction form
   82.50/123.72 = 28.36/x
3. Step 3: Cross multiply
   82.50x = 123.72 × 28.36
4. Step 4: Simplify right side
   82.50x = 3,508.70
5. Step 5: Solve for x
   x = 3,508.70/82.50
6. Step 6: Final answer
   x = 42.53