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Finding the Fourth Proportional to 421.05, 631.16 and 247.76

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Solution

The fourth proportional to 421.05, 631.16 and 247.76 is: 371.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.05 : 631.16 = 247.76 : x
  2. Step 2: Convert to fraction form
    421.05/631.16 = 247.76/x
  3. Step 3: Cross multiply
    421.05x = 631.16 × 247.76
  4. Step 4: Simplify right side
    421.05x = 156,373.67
  5. Step 5: Solve for x
    x = 156,373.67/421.05
  6. Step 6: Final answer
    x = 371.39

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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.