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Finding the Fourth Proportional to 643.14, 964.67 and 318.69

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Solution

The fourth proportional to 643.14, 964.67 and 318.69 is: 478.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.14 : 964.67 = 318.69 : x
  2. Step 2: Convert to fraction form
    643.14/964.67 = 318.69/x
  3. Step 3: Cross multiply
    643.14x = 964.67 × 318.69
  4. Step 4: Simplify right side
    643.14x = 307,429.09
  5. Step 5: Solve for x
    x = 307,429.09/643.14
  6. Step 6: Final answer
    x = 478.01

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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.