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Finding the Fourth Proportional to 800.47, 1,200.70 and 215.49

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Solution

The fourth proportional to 800.47, 1,200.70 and 215.49 is: 323.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.47 : 1,200.70 = 215.49 : x
  2. Step 2: Convert to fraction form
    800.47/1,200.70 = 215.49/x
  3. Step 3: Cross multiply
    800.47x = 1,200.70 × 215.49
  4. Step 4: Simplify right side
    800.47x = 258,738.84
  5. Step 5: Solve for x
    x = 258,738.84/800.47
  6. Step 6: Final answer
    x = 323.24

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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.