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Finding the Fourth Proportional to 7,200, 10,800 and 1,728

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Solution

The fourth proportional to 7,200, 10,800 and 1,728 is: 2,592

Step by Step Solution

  1. Step 1: Write the proportion equation
    7,200 : 10,800 = 1,728 : x
  2. Step 2: Convert to fraction form
    7,200/10,800 = 1,728/x
  3. Step 3: Cross multiply
    7,200x = 10,800 × 1,728
  4. Step 4: Simplify right side
    7,200x = 18,662,400
  5. Step 5: Solve for x
    x = 18,662,400/7,200
  6. Step 6: Final answer
    x = 2,592

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.