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Finding the Fourth Proportional to 640.73, 957.19 and 407.75

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Solution

The fourth proportional to 640.73, 957.19 and 407.75 is: 609.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.73 : 957.19 = 407.75 : x
  2. Step 2: Convert to fraction form
    640.73/957.19 = 407.75/x
  3. Step 3: Cross multiply
    640.73x = 957.19 × 407.75
  4. Step 4: Simplify right side
    640.73x = 390,294.22
  5. Step 5: Solve for x
    x = 390,294.22/640.73
  6. Step 6: Final answer
    x = 609.14

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.