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Finding the Fourth Proportional to 628.83, 867.65 and 380.30

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Solution

The fourth proportional to 628.83, 867.65 and 380.30 is: 524.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.83 : 867.65 = 380.30 : x
  2. Step 2: Convert to fraction form
    628.83/867.65 = 380.30/x
  3. Step 3: Cross multiply
    628.83x = 867.65 × 380.30
  4. Step 4: Simplify right side
    628.83x = 329,961.06
  5. Step 5: Solve for x
    x = 329,961.06/628.83
  6. Step 6: Final answer
    x = 524.72

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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.