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Finding the Fourth Proportional to 643.68, 964.90 and 424.47

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Solution

The fourth proportional to 643.68, 964.90 and 424.47 is: 636.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.68 : 964.90 = 424.47 : x
  2. Step 2: Convert to fraction form
    643.68/964.90 = 424.47/x
  3. Step 3: Cross multiply
    643.68x = 964.90 × 424.47
  4. Step 4: Simplify right side
    643.68x = 409,570.04
  5. Step 5: Solve for x
    x = 409,570.04/643.68
  6. Step 6: Final answer
    x = 636.29

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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.