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Finding the Fourth Proportional to 345.81, 518.58 and 215.87

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Solution

The fourth proportional to 345.81, 518.58 and 215.87 is: 323.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.81 : 518.58 = 215.87 : x
  2. Step 2: Convert to fraction form
    345.81/518.58 = 215.87/x
  3. Step 3: Cross multiply
    345.81x = 518.58 × 215.87
  4. Step 4: Simplify right side
    345.81x = 111,947.16
  5. Step 5: Solve for x
    x = 111,947.16/345.81
  6. Step 6: Final answer
    x = 323.72

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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.