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Finding the Fourth Proportional to 205.91, 309.10 and 172.07

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Solution

The fourth proportional to 205.91, 309.10 and 172.07 is: 258.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.91 : 309.10 = 172.07 : x
  2. Step 2: Convert to fraction form
    205.91/309.10 = 172.07/x
  3. Step 3: Cross multiply
    205.91x = 309.10 × 172.07
  4. Step 4: Simplify right side
    205.91x = 53,186.84
  5. Step 5: Solve for x
    x = 53,186.84/205.91
  6. Step 6: Final answer
    x = 258.30

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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.