Finding the Fourth Proportional to 72.15, 108.63 and 53.01

Step by Step Solution

1. Step 1: Write the proportion equation
   72.15 : 108.63 = 53.01 : x
2. Step 2: Convert to fraction form
   72.15/108.63 = 53.01/x
3. Step 3: Cross multiply
   72.15x = 108.63 × 53.01
4. Step 4: Simplify right side
   72.15x = 5,758.48
5. Step 5: Solve for x
   x = 5,758.48/72.15
6. Step 6: Final answer
   x = 79.81