Finding the Fourth Proportional to 13,090.19, 18,064.71 and 7,122.15

Step by Step Solution

1. Step 1: Write the proportion equation
   13,090.19 : 18,064.71 = 7,122.15 : x
2. Step 2: Convert to fraction form
   13,090.19/18,064.71 = 7,122.15/x
3. Step 3: Cross multiply
   13,090.19x = 18,064.71 × 7,122.15
4. Step 4: Simplify right side
   13,090.19x = 128,659,574.33
5. Step 5: Solve for x
   x = 128,659,574.33/13,090.19
6. Step 6: Final answer
   x = 9,828.71