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Finding the Fourth Proportional to 638.21, 957.44 and 199.45

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Solution

The fourth proportional to 638.21, 957.44 and 199.45 is: 299.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.21 : 957.44 = 199.45 : x
  2. Step 2: Convert to fraction form
    638.21/957.44 = 199.45/x
  3. Step 3: Cross multiply
    638.21x = 957.44 × 199.45
  4. Step 4: Simplify right side
    638.21x = 190,959.51
  5. Step 5: Solve for x
    x = 190,959.51/638.21
  6. Step 6: Final answer
    x = 299.21

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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.