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Finding the Fourth Proportional to 805.03, 1,109.46 and 639.18

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Solution

The fourth proportional to 805.03, 1,109.46 and 639.18 is: 880.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.03 : 1,109.46 = 639.18 : x
  2. Step 2: Convert to fraction form
    805.03/1,109.46 = 639.18/x
  3. Step 3: Cross multiply
    805.03x = 1,109.46 × 639.18
  4. Step 4: Simplify right side
    805.03x = 709,144.64
  5. Step 5: Solve for x
    x = 709,144.64/805.03
  6. Step 6: Final answer
    x = 880.89

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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.