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Finding the Fourth Proportional to 215.35, 320.49 and 213.19

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Solution

The fourth proportional to 215.35, 320.49 and 213.19 is: 317.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.35 : 320.49 = 213.19 : x
  2. Step 2: Convert to fraction form
    215.35/320.49 = 213.19/x
  3. Step 3: Cross multiply
    215.35x = 320.49 × 213.19
  4. Step 4: Simplify right side
    215.35x = 68,325.26
  5. Step 5: Solve for x
    x = 68,325.26/215.35
  6. Step 6: Final answer
    x = 317.28

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.