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Finding the Fourth Proportional to 642.43, 886.55 and 347.70

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Solution

The fourth proportional to 642.43, 886.55 and 347.70 is: 479.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.43 : 886.55 = 347.70 : x
  2. Step 2: Convert to fraction form
    642.43/886.55 = 347.70/x
  3. Step 3: Cross multiply
    642.43x = 886.55 × 347.70
  4. Step 4: Simplify right side
    642.43x = 308,252.66
  5. Step 5: Solve for x
    x = 308,252.66/642.43
  6. Step 6: Final answer
    x = 479.82

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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.