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Finding the Fourth Proportional to 209.45, 312.84 and 180.65

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Solution

The fourth proportional to 209.45, 312.84 and 180.65 is: 269.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.45 : 312.84 = 180.65 : x
  2. Step 2: Convert to fraction form
    209.45/312.84 = 180.65/x
  3. Step 3: Cross multiply
    209.45x = 312.84 × 180.65
  4. Step 4: Simplify right side
    209.45x = 56,513.64
  5. Step 5: Solve for x
    x = 56,513.64/209.45
  6. Step 6: Final answer
    x = 269.82

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.