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Finding the Fourth Proportional to 805.11, 1,111.07 and 490.39

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Solution

The fourth proportional to 805.11, 1,111.07 and 490.39 is: 676.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.11 : 1,111.07 = 490.39 : x
  2. Step 2: Convert to fraction form
    805.11/1,111.07 = 490.39/x
  3. Step 3: Cross multiply
    805.11x = 1,111.07 × 490.39
  4. Step 4: Simplify right side
    805.11x = 544,853.31
  5. Step 5: Solve for x
    x = 544,853.31/805.11
  6. Step 6: Final answer
    x = 676.75

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1.5x scale

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.