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Finding the Fourth Proportional to 643.42, 887.91 and 348.68

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Solution

The fourth proportional to 643.42, 887.91 and 348.68 is: 481.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.42 : 887.91 = 348.68 : x
  2. Step 2: Convert to fraction form
    643.42/887.91 = 348.68/x
  3. Step 3: Cross multiply
    643.42x = 887.91 × 348.68
  4. Step 4: Simplify right side
    643.42x = 309,592.02
  5. Step 5: Solve for x
    x = 309,592.02/643.42
  6. Step 6: Final answer
    x = 481.17

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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.