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Finding the Fourth Proportional to 639.80, 958.80 and 562.40

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Solution

The fourth proportional to 639.80, 958.80 and 562.40 is: 842.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.80 : 958.80 = 562.40 : x
  2. Step 2: Convert to fraction form
    639.80/958.80 = 562.40/x
  3. Step 3: Cross multiply
    639.80x = 958.80 × 562.40
  4. Step 4: Simplify right side
    639.80x = 539,229.12
  5. Step 5: Solve for x
    x = 539,229.12/639.80
  6. Step 6: Final answer
    x = 842.81

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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.