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Finding the Fourth Proportional to 628.21, 866.81 and 407.13

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Solution

The fourth proportional to 628.21, 866.81 and 407.13 is: 561.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.21 : 866.81 = 407.13 : x
  2. Step 2: Convert to fraction form
    628.21/866.81 = 407.13/x
  3. Step 3: Cross multiply
    628.21x = 866.81 × 407.13
  4. Step 4: Simplify right side
    628.21x = 352,902.32
  5. Step 5: Solve for x
    x = 352,902.32/628.21
  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.