Finding the Fourth Proportional to 61.34, 91.58 and 54.05

Step by Step Solution

1. Step 1: Write the proportion equation
   61.34 : 91.58 = 54.05 : x
2. Step 2: Convert to fraction form
   61.34/91.58 = 54.05/x
3. Step 3: Cross multiply
   61.34x = 91.58 × 54.05
4. Step 4: Simplify right side
   61.34x = 4,949.17
5. Step 5: Solve for x
   x = 4,949.17/61.34
6. Step 6: Final answer
   x = 80.69