Finding the Fourth Proportional to 91.62, 126.39 and 56.15

Step by Step Solution

1. Step 1: Write the proportion equation
   91.62 : 126.39 = 56.15 : x
2. Step 2: Convert to fraction form
   91.62/126.39 = 56.15/x
3. Step 3: Cross multiply
   91.62x = 126.39 × 56.15
4. Step 4: Simplify right side
   91.62x = 7,096.52
5. Step 5: Solve for x
   x = 7,096.52/91.62
6. Step 6: Final answer
   x = 77.46