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Finding the Fourth Proportional to 642.45, 886.57 and 347.71

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Solution

The fourth proportional to 642.45, 886.57 and 347.71 is: 479.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.45 : 886.57 = 347.71 : x
  2. Step 2: Convert to fraction form
    642.45/886.57 = 347.71/x
  3. Step 3: Cross multiply
    642.45x = 886.57 × 347.71
  4. Step 4: Simplify right side
    642.45x = 308,269.25
  5. Step 5: Solve for x
    x = 308,269.25/642.45
  6. Step 6: Final answer
    x = 479.83

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.