Finding the Fourth Proportional to 82.61, 123.91 and 28.50

Step by Step Solution

1. Step 1: Write the proportion equation
   82.61 : 123.91 = 28.50 : x
2. Step 2: Convert to fraction form
   82.61/123.91 = 28.50/x
3. Step 3: Cross multiply
   82.61x = 123.91 × 28.50
4. Step 4: Simplify right side
   82.61x = 3,531.36
5. Step 5: Solve for x
   x = 3,531.36/82.61
6. Step 6: Final answer
   x = 42.75