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Finding the Fourth Proportional to 643.50, 962.82 and 398.88

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Solution

The fourth proportional to 643.50, 962.82 and 398.88 is: 596.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.50 : 962.82 = 398.88 : x
  2. Step 2: Convert to fraction form
    643.50/962.82 = 398.88/x
  3. Step 3: Cross multiply
    643.50x = 962.82 × 398.88
  4. Step 4: Simplify right side
    643.50x = 384,049.64
  5. Step 5: Solve for x
    x = 384,049.64/643.50
  6. Step 6: Final answer
    x = 596.81

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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.