Finding the Fourth Proportional to 2,479.98, 3,720.42 and 836.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,479.98 : 3,720.42 = 836.40 : x
2. Step 2: Convert to fraction form
   2,479.98/3,720.42 = 836.40/x
3. Step 3: Cross multiply
   2,479.98x = 3,720.42 × 836.40
4. Step 4: Simplify right side
   2,479.98x = 3,111,759.29
5. Step 5: Solve for x
   x = 3,111,759.29/2,479.98
6. Step 6: Final answer
   x = 1,254.75