Finding the Fourth Proportional to 91.74, 126.72 and 86.34

Step by Step Solution

1. Step 1: Write the proportion equation
   91.74 : 126.72 = 86.34 : x
2. Step 2: Convert to fraction form
   91.74/126.72 = 86.34/x
3. Step 3: Cross multiply
   91.74x = 126.72 × 86.34
4. Step 4: Simplify right side
   91.74x = 10,941.00
5. Step 5: Solve for x
   x = 10,941.00/91.74
6. Step 6: Final answer
   x = 119.26