Finding the Fourth Proportional to 1,870.30, 2,578.35 and 1,279.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,870.30 : 2,578.35 = 1,279.90 : x
2. Step 2: Convert to fraction form
   1,870.30/2,578.35 = 1,279.90/x
3. Step 3: Cross multiply
   1,870.30x = 2,578.35 × 1,279.90
4. Step 4: Simplify right side
   1,870.30x = 3,300,030.17
5. Step 5: Solve for x
   x = 3,300,030.17/1,870.30
6. Step 6: Final answer
   x = 1,764.44