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Finding the Fourth Proportional to 643.02, 964.80 and 318.39

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Solution

The fourth proportional to 643.02, 964.80 and 318.39 is: 477.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.02 : 964.80 = 318.39 : x
  2. Step 2: Convert to fraction form
    643.02/964.80 = 318.39/x
  3. Step 3: Cross multiply
    643.02x = 964.80 × 318.39
  4. Step 4: Simplify right side
    643.02x = 307,182.67
  5. Step 5: Solve for x
    x = 307,182.67/643.02
  6. Step 6: Final answer
    x = 477.72

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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.