Finding the Fourth Proportional to 2,159.59, 2,980.48 and 1,215.38

Step by Step Solution

1. Step 1: Write the proportion equation
   2,159.59 : 2,980.48 = 1,215.38 : x
2. Step 2: Convert to fraction form
   2,159.59/2,980.48 = 1,215.38/x
3. Step 3: Cross multiply
   2,159.59x = 2,980.48 × 1,215.38
4. Step 4: Simplify right side
   2,159.59x = 3,622,415.78
5. Step 5: Solve for x
   x = 3,622,415.78/2,159.59
6. Step 6: Final answer
   x = 1,677.36