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Finding the Fourth Proportional to 500.10, 690.15 and 290.31

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Solution

The fourth proportional to 500.10, 690.15 and 290.31 is: 400.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.10 : 690.15 = 290.31 : x
  2. Step 2: Convert to fraction form
    500.10/690.15 = 290.31/x
  3. Step 3: Cross multiply
    500.10x = 690.15 × 290.31
  4. Step 4: Simplify right side
    500.10x = 200,357.45
  5. Step 5: Solve for x
    x = 200,357.45/500.10
  6. Step 6: Final answer
    x = 400.63

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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.