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Finding the Fourth Proportional to 285.28, 393.40 and 256.22

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Solution

The fourth proportional to 285.28, 393.40 and 256.22 is: 353.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.28 : 393.40 = 256.22 : x
  2. Step 2: Convert to fraction form
    285.28/393.40 = 256.22/x
  3. Step 3: Cross multiply
    285.28x = 393.40 × 256.22
  4. Step 4: Simplify right side
    285.28x = 100,797.29
  5. Step 5: Solve for x
    x = 100,797.29/285.28
  6. Step 6: Final answer
    x = 353.33

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.