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Finding the Fourth Proportional to 679.65, 1,019.63 and 387.29

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Solution

The fourth proportional to 679.65, 1,019.63 and 387.29 is: 581.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.65 : 1,019.63 = 387.29 : x
  2. Step 2: Convert to fraction form
    679.65/1,019.63 = 387.29/x
  3. Step 3: Cross multiply
    679.65x = 1,019.63 × 387.29
  4. Step 4: Simplify right side
    679.65x = 394,892.50
  5. Step 5: Solve for x
    x = 394,892.50/679.65
  6. Step 6: Final answer
    x = 581.02

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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.