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Finding the Fourth Proportional to 680.35, 1,020.71 and 290.36

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Solution

The fourth proportional to 680.35, 1,020.71 and 290.36 is: 435.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.35 : 1,020.71 = 290.36 : x
  2. Step 2: Convert to fraction form
    680.35/1,020.71 = 290.36/x
  3. Step 3: Cross multiply
    680.35x = 1,020.71 × 290.36
  4. Step 4: Simplify right side
    680.35x = 296,371.90
  5. Step 5: Solve for x
    x = 296,371.90/680.35
  6. Step 6: Final answer
    x = 435.62

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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.