Finding the Fourth Proportional to 72.84, 109.23 and 45.78

Step by Step Solution

1. Step 1: Write the proportion equation
   72.84 : 109.23 = 45.78 : x
2. Step 2: Convert to fraction form
   72.84/109.23 = 45.78/x
3. Step 3: Cross multiply
   72.84x = 109.23 × 45.78
4. Step 4: Simplify right side
   72.84x = 5,000.55
5. Step 5: Solve for x
   x = 5,000.55/72.84
6. Step 6: Final answer
   x = 68.65