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Finding the Fourth Proportional to 507.21, 699.90 and 286.15

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Solution

The fourth proportional to 507.21, 699.90 and 286.15 is: 394.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    507.21 : 699.90 = 286.15 : x
  2. Step 2: Convert to fraction form
    507.21/699.90 = 286.15/x
  3. Step 3: Cross multiply
    507.21x = 699.90 × 286.15
  4. Step 4: Simplify right side
    507.21x = 200,276.39
  5. Step 5: Solve for x
    x = 200,276.39/507.21
  6. Step 6: Final answer
    x = 394.86

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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.