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Finding the Fourth Proportional to 209.70, 314.55 and 190.80

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Solution

The fourth proportional to 209.70, 314.55 and 190.80 is: 286.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.70 : 314.55 = 190.80 : x
  2. Step 2: Convert to fraction form
    209.70/314.55 = 190.80/x
  3. Step 3: Cross multiply
    209.70x = 314.55 × 190.80
  4. Step 4: Simplify right side
    209.70x = 60,016.14
  5. Step 5: Solve for x
    x = 60,016.14/209.70
  6. Step 6: Final answer
    x = 286.20

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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.