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Finding the Fourth Proportional to 643, 964.08 and 318.28

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Solution

The fourth proportional to 643, 964.08 and 318.28 is: 477.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    643 : 964.08 = 318.28 : x
  2. Step 2: Convert to fraction form
    643/964.08 = 318.28/x
  3. Step 3: Cross multiply
    643x = 964.08 × 318.28
  4. Step 4: Simplify right side
    643x = 306,847.38
  5. Step 5: Solve for x
    x = 306,847.38/643
  6. Step 6: Final answer
    x = 477.21

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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.