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Finding the Fourth Proportional to 628.95, 867.81 and 407.91

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Solution

The fourth proportional to 628.95, 867.81 and 407.91 is: 562.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.95 : 867.81 = 407.91 : x
  2. Step 2: Convert to fraction form
    628.95/867.81 = 407.91/x
  3. Step 3: Cross multiply
    628.95x = 867.81 × 407.91
  4. Step 4: Simplify right side
    628.95x = 353,988.38
  5. Step 5: Solve for x
    x = 353,988.38/628.95
  6. Step 6: Final answer
    x = 562.82

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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.