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Finding the Fourth Proportional to 256.39, 353.51 and 209.65

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Solution

The fourth proportional to 256.39, 353.51 and 209.65 is: 289.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.39 : 353.51 = 209.65 : x
  2. Step 2: Convert to fraction form
    256.39/353.51 = 209.65/x
  3. Step 3: Cross multiply
    256.39x = 353.51 × 209.65
  4. Step 4: Simplify right side
    256.39x = 74,113.37
  5. Step 5: Solve for x
    x = 74,113.37/256.39
  6. Step 6: Final answer
    x = 289.06

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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.