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Finding the Fourth Proportional to 1,860, 2,791.28 and 644

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Solution

The fourth proportional to 1,860, 2,791.28 and 644 is: 966.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,860 : 2,791.28 = 644 : x
  2. Step 2: Convert to fraction form
    1,860/2,791.28 = 644/x
  3. Step 3: Cross multiply
    1,860x = 2,791.28 × 644
  4. Step 4: Simplify right side
    1,860x = 1,797,584.32
  5. Step 5: Solve for x
    x = 1,797,584.32/1,860
  6. Step 6: Final answer
    x = 966.44

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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.