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Finding the Fourth Proportional to 421.90, 582.28 and 256.14

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Solution

The fourth proportional to 421.90, 582.28 and 256.14 is: 353.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.90 : 582.28 = 256.14 : x
  2. Step 2: Convert to fraction form
    421.90/582.28 = 256.14/x
  3. Step 3: Cross multiply
    421.90x = 582.28 × 256.14
  4. Step 4: Simplify right side
    421.90x = 149,145.20
  5. Step 5: Solve for x
    x = 149,145.20/421.90
  6. Step 6: Final answer
    x = 353.51

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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.