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Finding the Fourth Proportional to 500.22, 690.21 and 290.39

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Solution

The fourth proportional to 500.22, 690.21 and 290.39 is: 400.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.22 : 690.21 = 290.39 : x
  2. Step 2: Convert to fraction form
    500.22/690.21 = 290.39/x
  3. Step 3: Cross multiply
    500.22x = 690.21 × 290.39
  4. Step 4: Simplify right side
    500.22x = 200,426.63
  5. Step 5: Solve for x
    x = 200,426.63/500.22
  6. Step 6: Final answer
    x = 400.68

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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.