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Finding the Fourth Proportional to 500.22, 690.31 and 290.40

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Solution

The fourth proportional to 500.22, 690.31 and 290.40 is: 400.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.22 : 690.31 = 290.40 : x
  2. Step 2: Convert to fraction form
    500.22/690.31 = 290.40/x
  3. Step 3: Cross multiply
    500.22x = 690.31 × 290.40
  4. Step 4: Simplify right side
    500.22x = 200,466.02
  5. Step 5: Solve for x
    x = 200,466.02/500.22
  6. Step 6: Final answer
    x = 400.76

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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.