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Finding the Fourth Proportional to 455.75, 628.72 and 290.21

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Solution

The fourth proportional to 455.75, 628.72 and 290.21 is: 400.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    455.75 : 628.72 = 290.21 : x
  2. Step 2: Convert to fraction form
    455.75/628.72 = 290.21/x
  3. Step 3: Cross multiply
    455.75x = 628.72 × 290.21
  4. Step 4: Simplify right side
    455.75x = 182,460.83
  5. Step 5: Solve for x
    x = 182,460.83/455.75
  6. Step 6: Final answer
    x = 400.35

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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.