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Finding the Fourth Proportional to 421.10, 631.76 and 247.91

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Solution

The fourth proportional to 421.10, 631.76 and 247.91 is: 371.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.10 : 631.76 = 247.91 : x
  2. Step 2: Convert to fraction form
    421.10/631.76 = 247.91/x
  3. Step 3: Cross multiply
    421.10x = 631.76 × 247.91
  4. Step 4: Simplify right side
    421.10x = 156,618.38
  5. Step 5: Solve for x
    x = 156,618.38/421.10
  6. Step 6: Final answer
    x = 371.93

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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.