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Finding the Fourth Proportional to 628.88, 867.60 and 408

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Solution

The fourth proportional to 628.88, 867.60 and 408 is: 562.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.88 : 867.60 = 408 : x
  2. Step 2: Convert to fraction form
    628.88/867.60 = 408/x
  3. Step 3: Cross multiply
    628.88x = 867.60 × 408
  4. Step 4: Simplify right side
    628.88x = 353,980.80
  5. Step 5: Solve for x
    x = 353,980.80/628.88
  6. Step 6: Final answer
    x = 562.87

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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.