Finding the Fourth Proportional to 2,119.89, 3,178.63 and 870.13

Step by Step Solution

1. Step 1: Write the proportion equation
   2,119.89 : 3,178.63 = 870.13 : x
2. Step 2: Convert to fraction form
   2,119.89/3,178.63 = 870.13/x
3. Step 3: Cross multiply
   2,119.89x = 3,178.63 × 870.13
4. Step 4: Simplify right side
   2,119.89x = 2,765,820.69
5. Step 5: Solve for x
   x = 2,765,820.69/2,119.89
6. Step 6: Final answer
   x = 1,304.70