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Finding the Fourth Proportional to 805.09, 1,207.68 and 285.02

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Solution

The fourth proportional to 805.09, 1,207.68 and 285.02 is: 427.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.09 : 1,207.68 = 285.02 : x
  2. Step 2: Convert to fraction form
    805.09/1,207.68 = 285.02/x
  3. Step 3: Cross multiply
    805.09x = 1,207.68 × 285.02
  4. Step 4: Simplify right side
    805.09x = 344,212.95
  5. Step 5: Solve for x
    x = 344,212.95/805.09
  6. Step 6: Final answer
    x = 427.55

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1.5x scale

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.