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Finding the Fourth Proportional to 647.39, 968.69 and 387.54

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Solution

The fourth proportional to 647.39, 968.69 and 387.54 is: 579.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.39 : 968.69 = 387.54 : x
  2. Step 2: Convert to fraction form
    647.39/968.69 = 387.54/x
  3. Step 3: Cross multiply
    647.39x = 968.69 × 387.54
  4. Step 4: Simplify right side
    647.39x = 375,407.09
  5. Step 5: Solve for x
    x = 375,407.09/647.39
  6. Step 6: Final answer
    x = 579.88

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.