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Finding the Fourth Proportional to 805.34, 1,208.12 and 257.58

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Solution

The fourth proportional to 805.34, 1,208.12 and 257.58 is: 386.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.34 : 1,208.12 = 257.58 : x
  2. Step 2: Convert to fraction form
    805.34/1,208.12 = 257.58/x
  3. Step 3: Cross multiply
    805.34x = 1,208.12 × 257.58
  4. Step 4: Simplify right side
    805.34x = 311,186.26
  5. Step 5: Solve for x
    x = 311,186.26/805.34
  6. Step 6: Final answer
    x = 386.40

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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.