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Finding the Fourth Proportional to 402.75, 555.80 and 218.75

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Solution

The fourth proportional to 402.75, 555.80 and 218.75 is: 301.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.75 : 555.80 = 218.75 : x
  2. Step 2: Convert to fraction form
    402.75/555.80 = 218.75/x
  3. Step 3: Cross multiply
    402.75x = 555.80 × 218.75
  4. Step 4: Simplify right side
    402.75x = 121,580.16
  5. Step 5: Solve for x
    x = 121,580.16/402.75
  6. Step 6: Final answer
    x = 301.88

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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.