Finding the Fourth Proportional to 72.87, 100.49 and 71.79

Step by Step Solution

1. Step 1: Write the proportion equation
   72.87 : 100.49 = 71.79 : x
2. Step 2: Convert to fraction form
   72.87/100.49 = 71.79/x
3. Step 3: Cross multiply
   72.87x = 100.49 × 71.79
4. Step 4: Simplify right side
   72.87x = 7,213.82
5. Step 5: Solve for x
   x = 7,213.82/72.87
6. Step 6: Final answer
   x = 99.00