Finding the Fourth Proportional to 127.31, 190.72 and 100.20

Step by Step Solution

1. Step 1: Write the proportion equation
   127.31 : 190.72 = 100.20 : x
2. Step 2: Convert to fraction form
   127.31/190.72 = 100.20/x
3. Step 3: Cross multiply
   127.31x = 190.72 × 100.20
4. Step 4: Simplify right side
   127.31x = 19,110.98
5. Step 5: Solve for x
   x = 19,110.98/127.31
6. Step 6: Final answer
   x = 150.12