Finding the Fourth Proportional to 72.84, 100.64 and 59.20

Step by Step Solution

1. Step 1: Write the proportion equation
   72.84 : 100.64 = 59.20 : x
2. Step 2: Convert to fraction form
   72.84/100.64 = 59.20/x
3. Step 3: Cross multiply
   72.84x = 100.64 × 59.20
4. Step 4: Simplify right side
   72.84x = 5,957.89
5. Step 5: Solve for x
   x = 5,957.89/72.84
6. Step 6: Final answer
   x = 81.79