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Finding the Fourth Proportional to 215.34, 322.80 and 87.18

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Solution

The fourth proportional to 215.34, 322.80 and 87.18 is: 130.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.34 : 322.80 = 87.18 : x
  2. Step 2: Convert to fraction form
    215.34/322.80 = 87.18/x
  3. Step 3: Cross multiply
    215.34x = 322.80 × 87.18
  4. Step 4: Simplify right side
    215.34x = 28,141.70
  5. Step 5: Solve for x
    x = 28,141.70/215.34
  6. Step 6: Final answer
    x = 130.68

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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.