Finding the Fourth Proportional to 128.69, 192.82 and 70.82

Step by Step Solution

1. Step 1: Write the proportion equation
   128.69 : 192.82 = 70.82 : x
2. Step 2: Convert to fraction form
   128.69/192.82 = 70.82/x
3. Step 3: Cross multiply
   128.69x = 192.82 × 70.82
4. Step 4: Simplify right side
   128.69x = 13,655.51
5. Step 5: Solve for x
   x = 13,655.51/128.69
6. Step 6: Final answer
   x = 106.12