Finding the Fourth Proportional to 91.69, 126.50 and 56.72

Step by Step Solution

1. Step 1: Write the proportion equation
   91.69 : 126.50 = 56.72 : x
2. Step 2: Convert to fraction form
   91.69/126.50 = 56.72/x
3. Step 3: Cross multiply
   91.69x = 126.50 × 56.72
4. Step 4: Simplify right side
   91.69x = 7,175.11
5. Step 5: Solve for x
   x = 7,175.11/91.69
6. Step 6: Final answer
   x = 78.26