Finding the Fourth Proportional to 107.10, 147.86 and 72.18

Step by Step Solution

1. Step 1: Write the proportion equation
   107.10 : 147.86 = 72.18 : x
2. Step 2: Convert to fraction form
   107.10/147.86 = 72.18/x
3. Step 3: Cross multiply
   107.10x = 147.86 × 72.18
4. Step 4: Simplify right side
   107.10x = 10,672.17
5. Step 5: Solve for x
   x = 10,672.17/107.10
6. Step 6: Final answer
   x = 99.65