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Finding the Fourth Proportional to 421.45, 628.34 and 410.81

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Solution

The fourth proportional to 421.45, 628.34 and 410.81 is: 612.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.45 : 628.34 = 410.81 : x
  2. Step 2: Convert to fraction form
    421.45/628.34 = 410.81/x
  3. Step 3: Cross multiply
    421.45x = 628.34 × 410.81
  4. Step 4: Simplify right side
    421.45x = 258,123.16
  5. Step 5: Solve for x
    x = 258,123.16/421.45
  6. Step 6: Final answer
    x = 612.47

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.