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Finding the Fourth Proportional to 345.28, 518.18 and 215.47

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Solution

The fourth proportional to 345.28, 518.18 and 215.47 is: 323.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.28 : 518.18 = 215.47 : x
  2. Step 2: Convert to fraction form
    345.28/518.18 = 215.47/x
  3. Step 3: Cross multiply
    345.28x = 518.18 × 215.47
  4. Step 4: Simplify right side
    345.28x = 111,649.87
  5. Step 5: Solve for x
    x = 111,649.87/345.28
  6. Step 6: Final answer
    x = 323.36

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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.