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Finding the Fourth Proportional to 649.80, 974.20 and 325.40

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Solution

The fourth proportional to 649.80, 974.20 and 325.40 is: 487.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.80 : 974.20 = 325.40 : x
  2. Step 2: Convert to fraction form
    649.80/974.20 = 325.40/x
  3. Step 3: Cross multiply
    649.80x = 974.20 × 325.40
  4. Step 4: Simplify right side
    649.80x = 317,004.68
  5. Step 5: Solve for x
    x = 317,004.68/649.80
  6. Step 6: Final answer
    x = 487.85

Related Problems

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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.