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Finding the Fourth Proportional to 378.42, 521.56 and 308.34

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Solution

The fourth proportional to 378.42, 521.56 and 308.34 is: 424.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.42 : 521.56 = 308.34 : x
  2. Step 2: Convert to fraction form
    378.42/521.56 = 308.34/x
  3. Step 3: Cross multiply
    378.42x = 521.56 × 308.34
  4. Step 4: Simplify right side
    378.42x = 160,817.81
  5. Step 5: Solve for x
    x = 160,817.81/378.42
  6. Step 6: Final answer
    x = 424.97

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.