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Finding the Fourth Proportional to 628.78, 867.72 and 352.78

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Solution

The fourth proportional to 628.78, 867.72 and 352.78 is: 486.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.78 : 867.72 = 352.78 : x
  2. Step 2: Convert to fraction form
    628.78/867.72 = 352.78/x
  3. Step 3: Cross multiply
    628.78x = 867.72 × 352.78
  4. Step 4: Simplify right side
    628.78x = 306,114.26
  5. Step 5: Solve for x
    x = 306,114.26/628.78
  6. Step 6: Final answer
    x = 486.84

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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.