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Finding the Fourth Proportional to 643.20, 887.64 and 363.51

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Solution

The fourth proportional to 643.20, 887.64 and 363.51 is: 501.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.20 : 887.64 = 363.51 : x
  2. Step 2: Convert to fraction form
    643.20/887.64 = 363.51/x
  3. Step 3: Cross multiply
    643.20x = 887.64 × 363.51
  4. Step 4: Simplify right side
    643.20x = 322,666.02
  5. Step 5: Solve for x
    x = 322,666.02/643.20
  6. Step 6: Final answer
    x = 501.66

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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.