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Finding the Fourth Proportional to 345.80, 517.55 and 215.89

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Solution

The fourth proportional to 345.80, 517.55 and 215.89 is: 323.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.80 : 517.55 = 215.89 : x
  2. Step 2: Convert to fraction form
    345.80/517.55 = 215.89/x
  3. Step 3: Cross multiply
    345.80x = 517.55 × 215.89
  4. Step 4: Simplify right side
    345.80x = 111,731.50
  5. Step 5: Solve for x
    x = 111,731.50/345.80
  6. Step 6: Final answer
    x = 323.11

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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.