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Finding the Fourth Proportional to 628.85, 942.60 and 320.78

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Solution

The fourth proportional to 628.85, 942.60 and 320.78 is: 480.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.85 : 942.60 = 320.78 : x
  2. Step 2: Convert to fraction form
    628.85/942.60 = 320.78/x
  3. Step 3: Cross multiply
    628.85x = 942.60 × 320.78
  4. Step 4: Simplify right side
    628.85x = 302,367.23
  5. Step 5: Solve for x
    x = 302,367.23/628.85
  6. Step 6: Final answer
    x = 480.83

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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.