Finding the Fourth Proportional to 98.20, 147.89 and 82.10

Step by Step Solution

1. Step 1: Write the proportion equation
   98.20 : 147.89 = 82.10 : x
2. Step 2: Convert to fraction form
   98.20/147.89 = 82.10/x
3. Step 3: Cross multiply
   98.20x = 147.89 × 82.10
4. Step 4: Simplify right side
   98.20x = 12,142.34
5. Step 5: Solve for x
   x = 12,142.34/98.20
6. Step 6: Final answer
   x = 123.65