Home / 1,321.70-1,982.55-397.40

Finding the Fourth Proportional to 1,321.70, 1,982.55 and 397.40

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Solution

The fourth proportional to 1,321.70, 1,982.55 and 397.40 is: 596.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.70 : 1,982.55 = 397.40 : x
  2. Step 2: Convert to fraction form
    1,321.70/1,982.55 = 397.40/x
  3. Step 3: Cross multiply
    1,321.70x = 1,982.55 × 397.40
  4. Step 4: Simplify right side
    1,321.70x = 787,865.37
  5. Step 5: Solve for x
    x = 787,865.37/1,321.70
  6. Step 6: Final answer
    x = 596.10

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Half scale
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Double scale
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Similar ratio
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1.5x scale

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.