Finding the Fourth Proportional to 82,128.32, 123,400.07 and 78,806.81

Step by Step Solution

1. Step 1: Write the proportion equation
   82,128.32 : 123,400.07 = 78,806.81 : x
2. Step 2: Convert to fraction form
   82,128.32/123,400.07 = 78,806.81/x
3. Step 3: Cross multiply
   82,128.32x = 123,400.07 × 78,806.81
4. Step 4: Simplify right side
   82,128.32x = 9,724,765,870.48
5. Step 5: Solve for x
   x = 9,724,765,870.48/82,128.32
6. Step 6: Final answer
   x = 118,409.41