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Finding the Fourth Proportional to 643.40, 965.85 and 335.60

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Solution

The fourth proportional to 643.40, 965.85 and 335.60 is: 503.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.40 : 965.85 = 335.60 : x
  2. Step 2: Convert to fraction form
    643.40/965.85 = 335.60/x
  3. Step 3: Cross multiply
    643.40x = 965.85 × 335.60
  4. Step 4: Simplify right side
    643.40x = 324,139.26
  5. Step 5: Solve for x
    x = 324,139.26/643.40
  6. Step 6: Final answer
    x = 503.79

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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.