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Finding the Fourth Proportional to 421.00, 631.50 and 258.19

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Solution

The fourth proportional to 421.00, 631.50 and 258.19 is: 387.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.00 : 631.50 = 258.19 : x
  2. Step 2: Convert to fraction form
    421.00/631.50 = 258.19/x
  3. Step 3: Cross multiply
    421.00x = 631.50 × 258.19
  4. Step 4: Simplify right side
    421.00x = 163,044.44
  5. Step 5: Solve for x
    x = 163,044.44/421.00
  6. Step 6: Final answer
    x = 387.28

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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.