Finding the Fourth Proportional to 91.02, 136.62 and 39.72

Step by Step Solution

1. Step 1: Write the proportion equation
   91.02 : 136.62 = 39.72 : x
2. Step 2: Convert to fraction form
   91.02/136.62 = 39.72/x
3. Step 3: Cross multiply
   91.02x = 136.62 × 39.72
4. Step 4: Simplify right side
   91.02x = 5,426.55
5. Step 5: Solve for x
   x = 5,426.55/91.02
6. Step 6: Final answer
   x = 59.62