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Finding the Fourth Proportional to 638.13, 957.55 and 345.63

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Solution

The fourth proportional to 638.13, 957.55 and 345.63 is: 518.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.13 : 957.55 = 345.63 : x
  2. Step 2: Convert to fraction form
    638.13/957.55 = 345.63/x
  3. Step 3: Cross multiply
    638.13x = 957.55 × 345.63
  4. Step 4: Simplify right side
    638.13x = 330,958.01
  5. Step 5: Solve for x
    x = 330,958.01/638.13
  6. Step 6: Final answer
    x = 518.64

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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.