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Finding the Fourth Proportional to 343.87, 515.30 and 256.79

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Solution

The fourth proportional to 343.87, 515.30 and 256.79 is: 384.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    343.87 : 515.30 = 256.79 : x
  2. Step 2: Convert to fraction form
    343.87/515.30 = 256.79/x
  3. Step 3: Cross multiply
    343.87x = 515.30 × 256.79
  4. Step 4: Simplify right side
    343.87x = 132,323.89
  5. Step 5: Solve for x
    x = 132,323.89/343.87
  6. Step 6: Final answer
    x = 384.81

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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.