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Finding the Fourth Proportional to 638.60, 957.15 and 631.76

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Solution

The fourth proportional to 638.60, 957.15 and 631.76 is: 946.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.60 : 957.15 = 631.76 : x
  2. Step 2: Convert to fraction form
    638.60/957.15 = 631.76/x
  3. Step 3: Cross multiply
    638.60x = 957.15 × 631.76
  4. Step 4: Simplify right side
    638.60x = 604,689.08
  5. Step 5: Solve for x
    x = 604,689.08/638.60
  6. Step 6: Final answer
    x = 946.90

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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.