Finding the Fourth Proportional to 74.76, 111.96 and 42.21

Step by Step Solution

1. Step 1: Write the proportion equation
   74.76 : 111.96 = 42.21 : x
2. Step 2: Convert to fraction form
   74.76/111.96 = 42.21/x
3. Step 3: Cross multiply
   74.76x = 111.96 × 42.21
4. Step 4: Simplify right side
   74.76x = 4,725.83
5. Step 5: Solve for x
   x = 4,725.83/74.76
6. Step 6: Final answer
   x = 63.21