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Finding the Fourth Proportional to 343.95, 515.40 and 256.87

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Solution

The fourth proportional to 343.95, 515.40 and 256.87 is: 384.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    343.95 : 515.40 = 256.87 : x
  2. Step 2: Convert to fraction form
    343.95/515.40 = 256.87/x
  3. Step 3: Cross multiply
    343.95x = 515.40 × 256.87
  4. Step 4: Simplify right side
    343.95x = 132,390.48
  5. Step 5: Solve for x
    x = 132,390.48/343.95
  6. Step 6: Final answer
    x = 384.92

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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.