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Finding the Fourth Proportional to 998.28, 1,497.42 and 420.75

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Solution

The fourth proportional to 998.28, 1,497.42 and 420.75 is: 631.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    998.28 : 1,497.42 = 420.75 : x
  2. Step 2: Convert to fraction form
    998.28/1,497.42 = 420.75/x
  3. Step 3: Cross multiply
    998.28x = 1,497.42 × 420.75
  4. Step 4: Simplify right side
    998.28x = 630,039.47
  5. Step 5: Solve for x
    x = 630,039.47/998.28
  6. Step 6: Final answer
    x = 631.13

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Half scale
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Double scale
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Similar ratio
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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.