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Finding the Fourth Proportional to 642.98, 887.28 and 363.20

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Solution

The fourth proportional to 642.98, 887.28 and 363.20 is: 501.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.98 : 887.28 = 363.20 : x
  2. Step 2: Convert to fraction form
    642.98/887.28 = 363.20/x
  3. Step 3: Cross multiply
    642.98x = 887.28 × 363.20
  4. Step 4: Simplify right side
    642.98x = 322,260.10
  5. Step 5: Solve for x
    x = 322,260.10/642.98
  6. Step 6: Final answer
    x = 501.20

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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.