Finding the Fourth Proportional to 83.91, 126.33 and 83.10

Step by Step Solution

1. Step 1: Write the proportion equation
   83.91 : 126.33 = 83.10 : x
2. Step 2: Convert to fraction form
   83.91/126.33 = 83.10/x
3. Step 3: Cross multiply
   83.91x = 126.33 × 83.10
4. Step 4: Simplify right side
   83.91x = 10,498.02
5. Step 5: Solve for x
   x = 10,498.02/83.91
6. Step 6: Final answer
   x = 125.11