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Finding the Fourth Proportional to 279.51, 385.89 and 209.00

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Solution

The fourth proportional to 279.51, 385.89 and 209.00 is: 288.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.51 : 385.89 = 209.00 : x
  2. Step 2: Convert to fraction form
    279.51/385.89 = 209.00/x
  3. Step 3: Cross multiply
    279.51x = 385.89 × 209.00
  4. Step 4: Simplify right side
    279.51x = 80,649.76
  5. Step 5: Solve for x
    x = 80,649.76/279.51
  6. Step 6: Final answer
    x = 288.54

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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.