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Finding the Fourth Proportional to 258.59, 387.33 and 215.15

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Solution

The fourth proportional to 258.59, 387.33 and 215.15 is: 322.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.59 : 387.33 = 215.15 : x
  2. Step 2: Convert to fraction form
    258.59/387.33 = 215.15/x
  3. Step 3: Cross multiply
    258.59x = 387.33 × 215.15
  4. Step 4: Simplify right side
    258.59x = 83,332.11
  5. Step 5: Solve for x
    x = 83,332.11/258.59
  6. Step 6: Final answer
    x = 322.26

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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.