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Finding the Fourth Proportional to 256.90, 354.72 and 207.70

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Solution

The fourth proportional to 256.90, 354.72 and 207.70 is: 286.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.90 : 354.72 = 207.70 : x
  2. Step 2: Convert to fraction form
    256.90/354.72 = 207.70/x
  3. Step 3: Cross multiply
    256.90x = 354.72 × 207.70
  4. Step 4: Simplify right side
    256.90x = 73,675.34
  5. Step 5: Solve for x
    x = 73,675.34/256.90
  6. Step 6: Final answer
    x = 286.79

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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.