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Finding the Fourth Proportional to 628.30, 867.04 and 379.81

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Solution

The fourth proportional to 628.30, 867.04 and 379.81 is: 524.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.30 : 867.04 = 379.81 : x
  2. Step 2: Convert to fraction form
    628.30/867.04 = 379.81/x
  3. Step 3: Cross multiply
    628.30x = 867.04 × 379.81
  4. Step 4: Simplify right side
    628.30x = 329,310.46
  5. Step 5: Solve for x
    x = 329,310.46/628.30
  6. Step 6: Final answer
    x = 524.13

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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.