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Finding the Fourth Proportional to 216.08, 321.40 and 215.39

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Solution

The fourth proportional to 216.08, 321.40 and 215.39 is: 320.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    216.08 : 321.40 = 215.39 : x
  2. Step 2: Convert to fraction form
    216.08/321.40 = 215.39/x
  3. Step 3: Cross multiply
    216.08x = 321.40 × 215.39
  4. Step 4: Simplify right side
    216.08x = 69,226.35
  5. Step 5: Solve for x
    x = 69,226.35/216.08
  6. Step 6: Final answer
    x = 320.37

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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.