Finding the Fourth Proportional to 42,823.16, 64,240.86 and 13,243.28

Step by Step Solution

1. Step 1: Write the proportion equation
   42,823.16 : 64,240.86 = 13,243.28 : x
2. Step 2: Convert to fraction form
   42,823.16/64,240.86 = 13,243.28/x
3. Step 3: Cross multiply
   42,823.16x = 64,240.86 × 13,243.28
4. Step 4: Simplify right side
   42,823.16x = 850,759,696.42
5. Step 5: Solve for x
   x = 850,759,696.42/42,823.16
6. Step 6: Final answer
   x = 19,866.81