Finding the Fourth Proportional to 2,155.51, 2,979.35 and 1,570.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,155.51 : 2,979.35 = 1,570.15 : x
2. Step 2: Convert to fraction form
   2,155.51/2,979.35 = 1,570.15/x
3. Step 3: Cross multiply
   2,155.51x = 2,979.35 × 1,570.15
4. Step 4: Simplify right side
   2,155.51x = 4,678,026.40
5. Step 5: Solve for x
   x = 4,678,026.40/2,155.51
6. Step 6: Final answer
   x = 2,170.26