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Finding the Fourth Proportional to 645.91, 968.77 and 213.07

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Solution

The fourth proportional to 645.91, 968.77 and 213.07 is: 319.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.91 : 968.77 = 213.07 : x
  2. Step 2: Convert to fraction form
    645.91/968.77 = 213.07/x
  3. Step 3: Cross multiply
    645.91x = 968.77 × 213.07
  4. Step 4: Simplify right side
    645.91x = 206,415.82
  5. Step 5: Solve for x
    x = 206,415.82/645.91
  6. Step 6: Final answer
    x = 319.57

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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.