Finding the Fourth Proportional to 100.84, 139.33 and 79.89

Step by Step Solution

1. Step 1: Write the proportion equation
   100.84 : 139.33 = 79.89 : x
2. Step 2: Convert to fraction form
   100.84/139.33 = 79.89/x
3. Step 3: Cross multiply
   100.84x = 139.33 × 79.89
4. Step 4: Simplify right side
   100.84x = 11,131.17
5. Step 5: Solve for x
   x = 11,131.17/100.84
6. Step 6: Final answer
   x = 110.39