Finding the Fourth Proportional to 102.02, 153.18 and 82.78

Step by Step Solution

1. Step 1: Write the proportion equation
   102.02 : 153.18 = 82.78 : x
2. Step 2: Convert to fraction form
   102.02/153.18 = 82.78/x
3. Step 3: Cross multiply
   102.02x = 153.18 × 82.78
4. Step 4: Simplify right side
   102.02x = 12,679.86
5. Step 5: Solve for x
   x = 12,679.86/102.02
6. Step 6: Final answer
   x = 124.29