Finding the Fourth Proportional to 69.92, 104.72 and 42.80

Step by Step Solution

1. Step 1: Write the proportion equation
   69.92 : 104.72 = 42.80 : x
2. Step 2: Convert to fraction form
   69.92/104.72 = 42.80/x
3. Step 3: Cross multiply
   69.92x = 104.72 × 42.80
4. Step 4: Simplify right side
   69.92x = 4,482.02
5. Step 5: Solve for x
   x = 4,482.02/69.92
6. Step 6: Final answer
   x = 64.10