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Finding the Fourth Proportional to 643.65, 964.86 and 297.21

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Solution

The fourth proportional to 643.65, 964.86 and 297.21 is: 445.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.65 : 964.86 = 297.21 : x
  2. Step 2: Convert to fraction form
    643.65/964.86 = 297.21/x
  3. Step 3: Cross multiply
    643.65x = 964.86 × 297.21
  4. Step 4: Simplify right side
    643.65x = 286,768.54
  5. Step 5: Solve for x
    x = 286,768.54/643.65
  6. Step 6: Final answer
    x = 445.54

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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.