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Finding the Fourth Proportional to 789.45, 1,089.12 and 494.91

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Solution

The fourth proportional to 789.45, 1,089.12 and 494.91 is: 682.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    789.45 : 1,089.12 = 494.91 : x
  2. Step 2: Convert to fraction form
    789.45/1,089.12 = 494.91/x
  3. Step 3: Cross multiply
    789.45x = 1,089.12 × 494.91
  4. Step 4: Simplify right side
    789.45x = 539,016.38
  5. Step 5: Solve for x
    x = 539,016.38/789.45
  6. Step 6: Final answer
    x = 682.77

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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.