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Finding the Fourth Proportional to 421.24, 631.46 and 256.30

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Solution

The fourth proportional to 421.24, 631.46 and 256.30 is: 384.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.24 : 631.46 = 256.30 : x
  2. Step 2: Convert to fraction form
    421.24/631.46 = 256.30/x
  3. Step 3: Cross multiply
    421.24x = 631.46 × 256.30
  4. Step 4: Simplify right side
    421.24x = 161,838.76
  5. Step 5: Solve for x
    x = 161,838.76/421.24
  6. Step 6: Final answer
    x = 384.20

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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.