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Finding the Fourth Proportional to 345.42, 517.73 and 128.84

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Solution

The fourth proportional to 345.42, 517.73 and 128.84 is: 193.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.42 : 517.73 = 128.84 : x
  2. Step 2: Convert to fraction form
    345.42/517.73 = 128.84/x
  3. Step 3: Cross multiply
    345.42x = 517.73 × 128.84
  4. Step 4: Simplify right side
    345.42x = 66,701.10
  5. Step 5: Solve for x
    x = 66,701.10/345.42
  6. Step 6: Final answer
    x = 193.10

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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.