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Finding the Fourth Proportional to 500.31, 690.36 and 279.21

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Solution

The fourth proportional to 500.31, 690.36 and 279.21 is: 385.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.31 : 690.36 = 279.21 : x
  2. Step 2: Convert to fraction form
    500.31/690.36 = 279.21/x
  3. Step 3: Cross multiply
    500.31x = 690.36 × 279.21
  4. Step 4: Simplify right side
    500.31x = 192,755.42
  5. Step 5: Solve for x
    x = 192,755.42/500.31
  6. Step 6: Final answer
    x = 385.27

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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.