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Finding the Fourth Proportional to 643.55, 965.32 and 406.16

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Solution

The fourth proportional to 643.55, 965.32 and 406.16 is: 609.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.55 : 965.32 = 406.16 : x
  2. Step 2: Convert to fraction form
    643.55/965.32 = 406.16/x
  3. Step 3: Cross multiply
    643.55x = 965.32 × 406.16
  4. Step 4: Simplify right side
    643.55x = 392,077.58
  5. Step 5: Solve for x
    x = 392,077.58/643.55
  6. Step 6: Final answer
    x = 609.25

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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.