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Finding the Fourth Proportional to 628.38, 866.79 and 407.25

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Solution

The fourth proportional to 628.38, 866.79 and 407.25 is: 561.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.38 : 866.79 = 407.25 : x
  2. Step 2: Convert to fraction form
    628.38/866.79 = 407.25/x
  3. Step 3: Cross multiply
    628.38x = 866.79 × 407.25
  4. Step 4: Simplify right side
    628.38x = 353,000.23
  5. Step 5: Solve for x
    x = 353,000.23/628.38
  6. Step 6: Final answer
    x = 561.76

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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.