Finding the Fourth Proportional to 89.72, 134.58 and 53.12

Step by Step Solution

1. Step 1: Write the proportion equation
   89.72 : 134.58 = 53.12 : x
2. Step 2: Convert to fraction form
   89.72/134.58 = 53.12/x
3. Step 3: Cross multiply
   89.72x = 134.58 × 53.12
4. Step 4: Simplify right side
   89.72x = 7,148.89
5. Step 5: Solve for x
   x = 7,148.89/89.72
6. Step 6: Final answer
   x = 79.68