Finding the Fourth Proportional to 127.40, 175.91 and 99.72

Step by Step Solution

1. Step 1: Write the proportion equation
   127.40 : 175.91 = 99.72 : x
2. Step 2: Convert to fraction form
   127.40/175.91 = 99.72/x
3. Step 3: Cross multiply
   127.40x = 175.91 × 99.72
4. Step 4: Simplify right side
   127.40x = 17,541.25
5. Step 5: Solve for x
   x = 17,541.25/127.40
6. Step 6: Final answer
   x = 137.69