Finding the Fourth Proportional to 42.18, 63.06 and 30.69

Step by Step Solution

1. Step 1: Write the proportion equation
   42.18 : 63.06 = 30.69 : x
2. Step 2: Convert to fraction form
   42.18/63.06 = 30.69/x
3. Step 3: Cross multiply
   42.18x = 63.06 × 30.69
4. Step 4: Simplify right side
   42.18x = 1,935.31
5. Step 5: Solve for x
   x = 1,935.31/42.18
6. Step 6: Final answer
   x = 45.88