Finding the Fourth Proportional to 105.10, 144.99 and 72.34

Step by Step Solution

1. Step 1: Write the proportion equation
   105.10 : 144.99 = 72.34 : x
2. Step 2: Convert to fraction form
   105.10/144.99 = 72.34/x
3. Step 3: Cross multiply
   105.10x = 144.99 × 72.34
4. Step 4: Simplify right side
   105.10x = 10,488.21
5. Step 5: Solve for x
   x = 10,488.21/105.10
6. Step 6: Final answer
   x = 99.80