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Finding the Fourth Proportional to 642.47, 886.63 and 362.78

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Solution

The fourth proportional to 642.47, 886.63 and 362.78 is: 500.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.47 : 886.63 = 362.78 : x
  2. Step 2: Convert to fraction form
    642.47/886.63 = 362.78/x
  3. Step 3: Cross multiply
    642.47x = 886.63 × 362.78
  4. Step 4: Simplify right side
    642.47x = 321,647.20
  5. Step 5: Solve for x
    x = 321,647.20/642.47
  6. Step 6: Final answer
    x = 500.64

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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.