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Finding the Fourth Proportional to 345.36, 517.68 and 128.84

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Solution

The fourth proportional to 345.36, 517.68 and 128.84 is: 193.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.36 : 517.68 = 128.84 : x
  2. Step 2: Convert to fraction form
    345.36/517.68 = 128.84/x
  3. Step 3: Cross multiply
    345.36x = 517.68 × 128.84
  4. Step 4: Simplify right side
    345.36x = 66,697.89
  5. Step 5: Solve for x
    x = 66,697.89/345.36
  6. Step 6: Final answer
    x = 193.13

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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.