Finding the Fourth Proportional to 42.76, 64.18 and 19.96

Step by Step Solution

1. Step 1: Write the proportion equation
   42.76 : 64.18 = 19.96 : x
2. Step 2: Convert to fraction form
   42.76/64.18 = 19.96/x
3. Step 3: Cross multiply
   42.76x = 64.18 × 19.96
4. Step 4: Simplify right side
   42.76x = 1,281.03
5. Step 5: Solve for x
   x = 1,281.03/42.76
6. Step 6: Final answer
   x = 29.96