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Finding the Fourth Proportional to 284.31, 426.51 and 257.40

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Solution

The fourth proportional to 284.31, 426.51 and 257.40 is: 386.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.31 : 426.51 = 257.40 : x
  2. Step 2: Convert to fraction form
    284.31/426.51 = 257.40/x
  3. Step 3: Cross multiply
    284.31x = 426.51 × 257.40
  4. Step 4: Simplify right side
    284.31x = 109,783.67
  5. Step 5: Solve for x
    x = 109,783.67/284.31
  6. Step 6: Final answer
    x = 386.14

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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.