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Finding the Fourth Proportional to 401.70, 602.55 and 209.70

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Solution

The fourth proportional to 401.70, 602.55 and 209.70 is: 314.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    401.70 : 602.55 = 209.70 : x
  2. Step 2: Convert to fraction form
    401.70/602.55 = 209.70/x
  3. Step 3: Cross multiply
    401.70x = 602.55 × 209.70
  4. Step 4: Simplify right side
    401.70x = 126,357.03
  5. Step 5: Solve for x
    x = 126,357.03/401.70
  6. Step 6: Final answer
    x = 314.55

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.