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Finding the Fourth Proportional to 421.11, 630.98 and 258.33

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Solution

The fourth proportional to 421.11, 630.98 and 258.33 is: 387.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.11 : 630.98 = 258.33 : x
  2. Step 2: Convert to fraction form
    421.11/630.98 = 258.33/x
  3. Step 3: Cross multiply
    421.11x = 630.98 × 258.33
  4. Step 4: Simplify right side
    421.11x = 162,999.77
  5. Step 5: Solve for x
    x = 162,999.77/421.11
  6. Step 6: Final answer
    x = 387.07

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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.