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Finding the Fourth Proportional to 451.40, 621.78 and 347.72

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Solution

The fourth proportional to 451.40, 621.78 and 347.72 is: 478.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    451.40 : 621.78 = 347.72 : x
  2. Step 2: Convert to fraction form
    451.40/621.78 = 347.72/x
  3. Step 3: Cross multiply
    451.40x = 621.78 × 347.72
  4. Step 4: Simplify right side
    451.40x = 216,205.34
  5. Step 5: Solve for x
    x = 216,205.34/451.40
  6. Step 6: Final answer
    x = 478.97

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.