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Finding the Fourth Proportional to 643.66, 965.43 and 319.24

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Solution

The fourth proportional to 643.66, 965.43 and 319.24 is: 478.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.66 : 965.43 = 319.24 : x
  2. Step 2: Convert to fraction form
    643.66/965.43 = 319.24/x
  3. Step 3: Cross multiply
    643.66x = 965.43 × 319.24
  4. Step 4: Simplify right side
    643.66x = 308,203.87
  5. Step 5: Solve for x
    x = 308,203.87/643.66
  6. Step 6: Final answer
    x = 478.83

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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.