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Finding the Fourth Proportional to 345.08, 515.14 and 320.78

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Solution

The fourth proportional to 345.08, 515.14 and 320.78 is: 478.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.08 : 515.14 = 320.78 : x
  2. Step 2: Convert to fraction form
    345.08/515.14 = 320.78/x
  3. Step 3: Cross multiply
    345.08x = 515.14 × 320.78
  4. Step 4: Simplify right side
    345.08x = 165,246.61
  5. Step 5: Solve for x
    x = 165,246.61/345.08
  6. Step 6: Final answer
    x = 478.86

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.