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Finding the Fourth Proportional to 500.40, 690.28 and 303.89

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Solution

The fourth proportional to 500.40, 690.28 and 303.89 is: 419.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.40 : 690.28 = 303.89 : x
  2. Step 2: Convert to fraction form
    500.40/690.28 = 303.89/x
  3. Step 3: Cross multiply
    500.40x = 690.28 × 303.89
  4. Step 4: Simplify right side
    500.40x = 209,764.98
  5. Step 5: Solve for x
    x = 209,764.98/500.40
  6. Step 6: Final answer
    x = 419.19

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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.