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Finding the Fourth Proportional to 354.61, 487.65 and 283.78

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Solution

The fourth proportional to 354.61, 487.65 and 283.78 is: 390.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    354.61 : 487.65 = 283.78 : x
  2. Step 2: Convert to fraction form
    354.61/487.65 = 283.78/x
  3. Step 3: Cross multiply
    354.61x = 487.65 × 283.78
  4. Step 4: Simplify right side
    354.61x = 138,385.32
  5. Step 5: Solve for x
    x = 138,385.32/354.61
  6. Step 6: Final answer
    x = 390.25

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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.