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Finding the Fourth Proportional to 868.70, 1,303.05 and 320.90

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Solution

The fourth proportional to 868.70, 1,303.05 and 320.90 is: 481.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    868.70 : 1,303.05 = 320.90 : x
  2. Step 2: Convert to fraction form
    868.70/1,303.05 = 320.90/x
  3. Step 3: Cross multiply
    868.70x = 1,303.05 × 320.90
  4. Step 4: Simplify right side
    868.70x = 418,148.75
  5. Step 5: Solve for x
    x = 418,148.75/868.70
  6. Step 6: Final answer
    x = 481.35

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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.