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Finding the Fourth Proportional to 500.45, 690.55 and 290.65

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Solution

The fourth proportional to 500.45, 690.55 and 290.65 is: 401.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.45 : 690.55 = 290.65 : x
  2. Step 2: Convert to fraction form
    500.45/690.55 = 290.65/x
  3. Step 3: Cross multiply
    500.45x = 690.55 × 290.65
  4. Step 4: Simplify right side
    500.45x = 200,704.90
  5. Step 5: Solve for x
    x = 200,704.90/500.45
  6. Step 6: Final answer
    x = 401.05

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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.