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Finding the Fourth Proportional to 279.75, 386.34 and 218.31

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Solution

The fourth proportional to 279.75, 386.34 and 218.31 is: 301.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.75 : 386.34 = 218.31 : x
  2. Step 2: Convert to fraction form
    279.75/386.34 = 218.31/x
  3. Step 3: Cross multiply
    279.75x = 386.34 × 218.31
  4. Step 4: Simplify right side
    279.75x = 84,341.89
  5. Step 5: Solve for x
    x = 84,341.89/279.75
  6. Step 6: Final answer
    x = 301.49

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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.