Finding the Fourth Proportional to 1,415.16, 2,120.00 and 1,123.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,415.16 : 2,120.00 = 1,123.20 : x
2. Step 2: Convert to fraction form
   1,415.16/2,120.00 = 1,123.20/x
3. Step 3: Cross multiply
   1,415.16x = 2,120.00 × 1,123.20
4. Step 4: Simplify right side
   1,415.16x = 2,381,178.38
5. Step 5: Solve for x
   x = 2,381,178.38/1,415.16
6. Step 6: Final answer
   x = 1,682.62