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Finding the Fourth Proportional to 338.40, 507.60 and 257.67

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Solution

The fourth proportional to 338.40, 507.60 and 257.67 is: 386.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.40 : 507.60 = 257.67 : x
  2. Step 2: Convert to fraction form
    338.40/507.60 = 257.67/x
  3. Step 3: Cross multiply
    338.40x = 507.60 × 257.67
  4. Step 4: Simplify right side
    338.40x = 130,793.29
  5. Step 5: Solve for x
    x = 130,793.29/338.40
  6. Step 6: Final answer
    x = 386.51

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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.