Finding the Fourth Proportional to 72.21, 99.71 and 50.42

Step by Step Solution

1. Step 1: Write the proportion equation
   72.21 : 99.71 = 50.42 : x
2. Step 2: Convert to fraction form
   72.21/99.71 = 50.42/x
3. Step 3: Cross multiply
   72.21x = 99.71 × 50.42
4. Step 4: Simplify right side
   72.21x = 5,026.63
5. Step 5: Solve for x
   x = 5,026.63/72.21
6. Step 6: Final answer
   x = 69.61