Finding the Fourth Proportional to 83.12, 124.74 and 42.50

Step by Step Solution

1. Step 1: Write the proportion equation
   83.12 : 124.74 = 42.50 : x
2. Step 2: Convert to fraction form
   83.12/124.74 = 42.50/x
3. Step 3: Cross multiply
   83.12x = 124.74 × 42.50
4. Step 4: Simplify right side
   83.12x = 5,301.45
5. Step 5: Solve for x
   x = 5,301.45/83.12
6. Step 6: Final answer
   x = 63.78