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Finding the Fourth Proportional to 638.07, 957.10 and 420.07

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Solution

The fourth proportional to 638.07, 957.10 and 420.07 is: 630.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.07 : 957.10 = 420.07 : x
  2. Step 2: Convert to fraction form
    638.07/957.10 = 420.07/x
  3. Step 3: Cross multiply
    638.07x = 957.10 × 420.07
  4. Step 4: Simplify right side
    638.07x = 402,049.00
  5. Step 5: Solve for x
    x = 402,049.00/638.07
  6. Step 6: Final answer
    x = 630.10

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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.