Finding the Fourth Proportional to 2,160.00, 2,980.55 and 1,215.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,160.00 : 2,980.55 = 1,215.89 : x
2. Step 2: Convert to fraction form
   2,160.00/2,980.55 = 1,215.89/x
3. Step 3: Cross multiply
   2,160.00x = 2,980.55 × 1,215.89
4. Step 4: Simplify right side
   2,160.00x = 3,624,005.03
5. Step 5: Solve for x
   x = 3,624,005.03/2,160.00
6. Step 6: Final answer
   x = 1,677.78