Finding the Fourth Proportional to 105,271.08, 145,303.38 and 64,991.40

Step by Step Solution

1. Step 1: Write the proportion equation
   105,271.08 : 145,303.38 = 64,991.40 : x
2. Step 2: Convert to fraction form
   105,271.08/145,303.38 = 64,991.40/x
3. Step 3: Cross multiply
   105,271.08x = 145,303.38 × 64,991.40
4. Step 4: Simplify right side
   105,271.08x = 9,443,470,090.93
5. Step 5: Solve for x
   x = 9,443,470,090.93/105,271.08
6. Step 6: Final answer
   x = 89,706.21