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Finding the Fourth Proportional to 205.12, 307.20 and 123.76

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Solution

The fourth proportional to 205.12, 307.20 and 123.76 is: 185.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.12 : 307.20 = 123.76 : x
  2. Step 2: Convert to fraction form
    205.12/307.20 = 123.76/x
  3. Step 3: Cross multiply
    205.12x = 307.20 × 123.76
  4. Step 4: Simplify right side
    205.12x = 38,019.07
  5. Step 5: Solve for x
    x = 38,019.07/205.12
  6. Step 6: Final answer
    x = 185.35

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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.