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Finding the Fourth Proportional to 643.43, 965.58 and 400.09

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Solution

The fourth proportional to 643.43, 965.58 and 400.09 is: 600.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.43 : 965.58 = 400.09 : x
  2. Step 2: Convert to fraction form
    643.43/965.58 = 400.09/x
  3. Step 3: Cross multiply
    643.43x = 965.58 × 400.09
  4. Step 4: Simplify right side
    643.43x = 386,318.90
  5. Step 5: Solve for x
    x = 386,318.90/643.43
  6. Step 6: Final answer
    x = 600.41

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1.5x scale

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.