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Finding the Fourth Proportional to 628.29, 867.20 and 379.80

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Solution

The fourth proportional to 628.29, 867.20 and 379.80 is: 524.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.29 : 867.20 = 379.80 : x
  2. Step 2: Convert to fraction form
    628.29/867.20 = 379.80/x
  3. Step 3: Cross multiply
    628.29x = 867.20 × 379.80
  4. Step 4: Simplify right side
    628.29x = 329,360.66
  5. Step 5: Solve for x
    x = 329,360.66/628.29
  6. Step 6: Final answer
    x = 524.22

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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.