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Finding the Fourth Proportional to 2,840, 3,919.20 and 2,340.80

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Solution

The fourth proportional to 2,840, 3,919.20 and 2,340.80 is: 3,230.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,840 : 3,919.20 = 2,340.80 : x
  2. Step 2: Convert to fraction form
    2,840/3,919.20 = 2,340.80/x
  3. Step 3: Cross multiply
    2,840x = 3,919.20 × 2,340.80
  4. Step 4: Simplify right side
    2,840x = 9,174,063.36
  5. Step 5: Solve for x
    x = 9,174,063.36/2,840
  6. Step 6: Final answer
    x = 3,230.30

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.