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Finding the Fourth Proportional to 279.79, 386.48 and 215.09

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Solution

The fourth proportional to 279.79, 386.48 and 215.09 is: 297.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.79 : 386.48 = 215.09 : x
  2. Step 2: Convert to fraction form
    279.79/386.48 = 215.09/x
  3. Step 3: Cross multiply
    279.79x = 386.48 × 215.09
  4. Step 4: Simplify right side
    279.79x = 83,127.98
  5. Step 5: Solve for x
    x = 83,127.98/279.79
  6. Step 6: Final answer
    x = 297.11

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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.