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Finding the Fourth Proportional to 209.17, 314.07 and 128.35

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Solution

The fourth proportional to 209.17, 314.07 and 128.35 is: 192.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.17 : 314.07 = 128.35 : x
  2. Step 2: Convert to fraction form
    209.17/314.07 = 128.35/x
  3. Step 3: Cross multiply
    209.17x = 314.07 × 128.35
  4. Step 4: Simplify right side
    209.17x = 40,310.88
  5. Step 5: Solve for x
    x = 40,310.88/209.17
  6. Step 6: Final answer
    x = 192.72

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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.