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Finding the Fourth Proportional to 628.42, 942.72 and 320.47

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Solution

The fourth proportional to 628.42, 942.72 and 320.47 is: 480.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.42 : 942.72 = 320.47 : x
  2. Step 2: Convert to fraction form
    628.42/942.72 = 320.47/x
  3. Step 3: Cross multiply
    628.42x = 942.72 × 320.47
  4. Step 4: Simplify right side
    628.42x = 302,113.48
  5. Step 5: Solve for x
    x = 302,113.48/628.42
  6. Step 6: Final answer
    x = 480.75

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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.