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Finding the Fourth Proportional to 642.30, 886.38 and 347.57

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Solution

The fourth proportional to 642.30, 886.38 and 347.57 is: 479.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.30 : 886.38 = 347.57 : x
  2. Step 2: Convert to fraction form
    642.30/886.38 = 347.57/x
  3. Step 3: Cross multiply
    642.30x = 886.38 × 347.57
  4. Step 4: Simplify right side
    642.30x = 308,081.27
  5. Step 5: Solve for x
    x = 308,081.27/642.30
  6. Step 6: Final answer
    x = 479.65

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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.