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Finding the Fourth Proportional to 638.79, 957.47 and 314.39

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Solution

The fourth proportional to 638.79, 957.47 and 314.39 is: 471.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.79 : 957.47 = 314.39 : x
  2. Step 2: Convert to fraction form
    638.79/957.47 = 314.39/x
  3. Step 3: Cross multiply
    638.79x = 957.47 × 314.39
  4. Step 4: Simplify right side
    638.79x = 301,012.63
  5. Step 5: Solve for x
    x = 301,012.63/638.79
  6. Step 6: Final answer
    x = 471.22

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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.