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Finding the Fourth Proportional to 680.34, 1,020.89 and 290.30

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Solution

The fourth proportional to 680.34, 1,020.89 and 290.30 is: 435.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.34 : 1,020.89 = 290.30 : x
  2. Step 2: Convert to fraction form
    680.34/1,020.89 = 290.30/x
  3. Step 3: Cross multiply
    680.34x = 1,020.89 × 290.30
  4. Step 4: Simplify right side
    680.34x = 296,358.90
  5. Step 5: Solve for x
    x = 296,358.90/680.34
  6. Step 6: Final answer
    x = 435.61

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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.