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Finding the Fourth Proportional to 378.43, 521.51 and 308.67

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Solution

The fourth proportional to 378.43, 521.51 and 308.67 is: 425.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.43 : 521.51 = 308.67 : x
  2. Step 2: Convert to fraction form
    378.43/521.51 = 308.67/x
  3. Step 3: Cross multiply
    378.43x = 521.51 × 308.67
  4. Step 4: Simplify right side
    378.43x = 160,970.99
  5. Step 5: Solve for x
    x = 160,970.99/378.43
  6. Step 6: Final answer
    x = 425.37

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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.