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Finding the Fourth Proportional to 668.81, 1,003.61 and 257.98

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Solution

The fourth proportional to 668.81, 1,003.61 and 257.98 is: 387.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.81 : 1,003.61 = 257.98 : x
  2. Step 2: Convert to fraction form
    668.81/1,003.61 = 257.98/x
  3. Step 3: Cross multiply
    668.81x = 1,003.61 × 257.98
  4. Step 4: Simplify right side
    668.81x = 258,909.44
  5. Step 5: Solve for x
    x = 258,909.44/668.81
  6. Step 6: Final answer
    x = 387.12

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.