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Finding the Fourth Proportional to 921.38, 1,270.08 and 810.20

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Solution

The fourth proportional to 921.38, 1,270.08 and 810.20 is: 1,116.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    921.38 : 1,270.08 = 810.20 : x
  2. Step 2: Convert to fraction form
    921.38/1,270.08 = 810.20/x
  3. Step 3: Cross multiply
    921.38x = 1,270.08 × 810.20
  4. Step 4: Simplify right side
    921.38x = 1,029,021.99
  5. Step 5: Solve for x
    x = 1,029,021.99/921.38
  6. Step 6: Final answer
    x = 1,116.83

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 (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.