Finding the Fourth Proportional to 72.24, 99.72 and 55.94

Step by Step Solution

1. Step 1: Write the proportion equation
   72.24 : 99.72 = 55.94 : x
2. Step 2: Convert to fraction form
   72.24/99.72 = 55.94/x
3. Step 3: Cross multiply
   72.24x = 99.72 × 55.94
4. Step 4: Simplify right side
   72.24x = 5,577.84
5. Step 5: Solve for x
   x = 5,577.84/72.24
6. Step 6: Final answer
   x = 77.21