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Finding the Fourth Proportional to 500.21, 690.28 and 279.15

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Solution

The fourth proportional to 500.21, 690.28 and 279.15 is: 385.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.21 : 690.28 = 279.15 : x
  2. Step 2: Convert to fraction form
    500.21/690.28 = 279.15/x
  3. Step 3: Cross multiply
    500.21x = 690.28 × 279.15
  4. Step 4: Simplify right side
    500.21x = 192,691.66
  5. Step 5: Solve for x
    x = 192,691.66/500.21
  6. Step 6: Final answer
    x = 385.22

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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.