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Finding the Fourth Proportional to 421.49, 630.65 and 248.21

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Solution

The fourth proportional to 421.49, 630.65 and 248.21 is: 371.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.49 : 630.65 = 248.21 : x
  2. Step 2: Convert to fraction form
    421.49/630.65 = 248.21/x
  3. Step 3: Cross multiply
    421.49x = 630.65 × 248.21
  4. Step 4: Simplify right side
    421.49x = 156,537.02
  5. Step 5: Solve for x
    x = 156,537.02/421.49
  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.