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Finding the Fourth Proportional to 628.78, 867.69 and 380.08

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Solution

The fourth proportional to 628.78, 867.69 and 380.08 is: 524.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.78 : 867.69 = 380.08 : x
  2. Step 2: Convert to fraction form
    628.78/867.69 = 380.08/x
  3. Step 3: Cross multiply
    628.78x = 867.69 × 380.08
  4. Step 4: Simplify right side
    628.78x = 329,789.45
  5. Step 5: Solve for x
    x = 329,789.45/628.78
  6. Step 6: Final answer
    x = 524.49

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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.