Finding the Fourth Proportional to 142.50, 213.69 and 49.92

Step by Step Solution

1. Step 1: Write the proportion equation
   142.50 : 213.69 = 49.92 : x
2. Step 2: Convert to fraction form
   142.50/213.69 = 49.92/x
3. Step 3: Cross multiply
   142.50x = 213.69 × 49.92
4. Step 4: Simplify right side
   142.50x = 10,667.40
5. Step 5: Solve for x
   x = 10,667.40/142.50
6. Step 6: Final answer
   x = 74.86