Finding the Fourth Proportional to 1,415.89, 2,134.69 and 1,320.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,415.89 : 2,134.69 = 1,320.60 : x
2. Step 2: Convert to fraction form
   1,415.89/2,134.69 = 1,320.60/x
3. Step 3: Cross multiply
   1,415.89x = 2,134.69 × 1,320.60
4. Step 4: Simplify right side
   1,415.89x = 2,819,068.31
5. Step 5: Solve for x
   x = 2,819,068.31/1,415.89
6. Step 6: Final answer
   x = 1,991.03