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Finding the Fourth Proportional to 378.66, 520.34 and 308.58

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Solution

The fourth proportional to 378.66, 520.34 and 308.58 is: 424.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.66 : 520.34 = 308.58 : x
  2. Step 2: Convert to fraction form
    378.66/520.34 = 308.58/x
  3. Step 3: Cross multiply
    378.66x = 520.34 × 308.58
  4. Step 4: Simplify right side
    378.66x = 160,563.02
  5. Step 5: Solve for x
    x = 160,563.02/378.66
  6. Step 6: Final answer
    x = 424.03

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.