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Finding the Fourth Proportional to 628.81, 866.79 and 471.20

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Solution

The fourth proportional to 628.81, 866.79 and 471.20 is: 649.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.81 : 866.79 = 471.20 : x
  2. Step 2: Convert to fraction form
    628.81/866.79 = 471.20/x
  3. Step 3: Cross multiply
    628.81x = 866.79 × 471.20
  4. Step 4: Simplify right side
    628.81x = 408,427.11
  5. Step 5: Solve for x
    x = 408,427.11/628.81
  6. Step 6: Final answer
    x = 649.53

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.