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Finding the Fourth Proportional to 639.19, 957.13 and 443.90

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Solution

The fourth proportional to 639.19, 957.13 and 443.90 is: 664.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.19 : 957.13 = 443.90 : x
  2. Step 2: Convert to fraction form
    639.19/957.13 = 443.90/x
  3. Step 3: Cross multiply
    639.19x = 957.13 × 443.90
  4. Step 4: Simplify right side
    639.19x = 424,870.01
  5. Step 5: Solve for x
    x = 424,870.01/639.19
  6. Step 6: Final answer
    x = 664.70

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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.