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Finding the Fourth Proportional to 853.69, 1,280.40 and 305.77

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Solution

The fourth proportional to 853.69, 1,280.40 and 305.77 is: 458.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    853.69 : 1,280.40 = 305.77 : x
  2. Step 2: Convert to fraction form
    853.69/1,280.40 = 305.77/x
  3. Step 3: Cross multiply
    853.69x = 1,280.40 × 305.77
  4. Step 4: Simplify right side
    853.69x = 391,507.91
  5. Step 5: Solve for x
    x = 391,507.91/853.69
  6. Step 6: Final answer
    x = 458.61

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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.