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Finding the Fourth Proportional to 613.77, 920.62 and 408.28

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Solution

The fourth proportional to 613.77, 920.62 and 408.28 is: 612.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.77 : 920.62 = 408.28 : x
  2. Step 2: Convert to fraction form
    613.77/920.62 = 408.28/x
  3. Step 3: Cross multiply
    613.77x = 920.62 × 408.28
  4. Step 4: Simplify right side
    613.77x = 375,870.73
  5. Step 5: Solve for x
    x = 375,870.73/613.77
  6. Step 6: Final answer
    x = 612.40

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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.