Finding the Fourth Proportional to 72.95, 100.70 and 50.21

Step by Step Solution

1. Step 1: Write the proportion equation
   72.95 : 100.70 = 50.21 : x
2. Step 2: Convert to fraction form
   72.95/100.70 = 50.21/x
3. Step 3: Cross multiply
   72.95x = 100.70 × 50.21
4. Step 4: Simplify right side
   72.95x = 5,056.15
5. Step 5: Solve for x
   x = 5,056.15/72.95
6. Step 6: Final answer
   x = 69.31