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Finding the Fourth Proportional to 638.15, 957.11 and 291.40

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Solution

The fourth proportional to 638.15, 957.11 and 291.40 is: 437.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.15 : 957.11 = 291.40 : x
  2. Step 2: Convert to fraction form
    638.15/957.11 = 291.40/x
  3. Step 3: Cross multiply
    638.15x = 957.11 × 291.40
  4. Step 4: Simplify right side
    638.15x = 278,899.64
  5. Step 5: Solve for x
    x = 278,899.64/638.15
  6. Step 6: Final answer
    x = 437.05

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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.