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Finding the Fourth Proportional to 628.71, 867.61 and 407.65

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Solution

The fourth proportional to 628.71, 867.61 and 407.65 is: 562.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.71 : 867.61 = 407.65 : x
  2. Step 2: Convert to fraction form
    628.71/867.61 = 407.65/x
  3. Step 3: Cross multiply
    628.71x = 867.61 × 407.65
  4. Step 4: Simplify right side
    628.71x = 353,681.22
  5. Step 5: Solve for x
    x = 353,681.22/628.71
  6. Step 6: Final answer
    x = 562.55

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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.