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Finding the Fourth Proportional to 639.12, 954.02 and 548.40

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Solution

The fourth proportional to 639.12, 954.02 and 548.40 is: 818.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.12 : 954.02 = 548.40 : x
  2. Step 2: Convert to fraction form
    639.12/954.02 = 548.40/x
  3. Step 3: Cross multiply
    639.12x = 954.02 × 548.40
  4. Step 4: Simplify right side
    639.12x = 523,187.97
  5. Step 5: Solve for x
    x = 523,187.97/639.12
  6. Step 6: Final answer
    x = 818.60

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.