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Finding the Fourth Proportional to 418.95, 628.08 and 256.29

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Solution

The fourth proportional to 418.95, 628.08 and 256.29 is: 384.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.95 : 628.08 = 256.29 : x
  2. Step 2: Convert to fraction form
    418.95/628.08 = 256.29/x
  3. Step 3: Cross multiply
    418.95x = 628.08 × 256.29
  4. Step 4: Simplify right side
    418.95x = 160,969.79
  5. Step 5: Solve for x
    x = 160,969.79/418.95
  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.