Finding the Fourth Proportional to 72.79, 100.88 and 71.42

Step by Step Solution

1. Step 1: Write the proportion equation
   72.79 : 100.88 = 71.42 : x
2. Step 2: Convert to fraction form
   72.79/100.88 = 71.42/x
3. Step 3: Cross multiply
   72.79x = 100.88 × 71.42
4. Step 4: Simplify right side
   72.79x = 7,204.67
5. Step 5: Solve for x
   x = 7,204.67/72.79
6. Step 6: Final answer
   x = 98.98