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Finding the Fourth Proportional to 1,638.60, 2,458.08 and 664.80

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Solution

The fourth proportional to 1,638.60, 2,458.08 and 664.80 is: 997.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,638.60 : 2,458.08 = 664.80 : x
  2. Step 2: Convert to fraction form
    1,638.60/2,458.08 = 664.80/x
  3. Step 3: Cross multiply
    1,638.60x = 2,458.08 × 664.80
  4. Step 4: Simplify right side
    1,638.60x = 1,634,131.58
  5. Step 5: Solve for x
    x = 1,634,131.58/1,638.60
  6. Step 6: Final answer
    x = 997.27

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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.