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Finding the Fourth Proportional to 642.30, 886.39 and 347.58

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Solution

The fourth proportional to 642.30, 886.39 and 347.58 is: 479.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.30 : 886.39 = 347.58 : x
  2. Step 2: Convert to fraction form
    642.30/886.39 = 347.58/x
  3. Step 3: Cross multiply
    642.30x = 886.39 × 347.58
  4. Step 4: Simplify right side
    642.30x = 308,089.08
  5. Step 5: Solve for x
    x = 308,089.08/642.30
  6. Step 6: Final answer
    x = 479.66

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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.