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Finding the Fourth Proportional to 418.79, 627.86 and 256.28

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Solution

The fourth proportional to 418.79, 627.86 and 256.28 is: 384.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.79 : 627.86 = 256.28 : x
  2. Step 2: Convert to fraction form
    418.79/627.86 = 256.28/x
  3. Step 3: Cross multiply
    418.79x = 627.86 × 256.28
  4. Step 4: Simplify right side
    418.79x = 160,903.54
  5. Step 5: Solve for x
    x = 160,903.54/418.79
  6. Step 6: Final answer
    x = 384.22

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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.