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Finding the Fourth Proportional to 345.40, 520.47 and 285.86

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Solution

The fourth proportional to 345.40, 520.47 and 285.86 is: 430.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.40 : 520.47 = 285.86 : x
  2. Step 2: Convert to fraction form
    345.40/520.47 = 285.86/x
  3. Step 3: Cross multiply
    345.40x = 520.47 × 285.86
  4. Step 4: Simplify right side
    345.40x = 148,781.55
  5. Step 5: Solve for x
    x = 148,781.55/345.40
  6. Step 6: Final answer
    x = 430.75

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.