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Finding the Fourth Proportional to 811.38, 1,120.41 and 636.42

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Solution

The fourth proportional to 811.38, 1,120.41 and 636.42 is: 878.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.38 : 1,120.41 = 636.42 : x
  2. Step 2: Convert to fraction form
    811.38/1,120.41 = 636.42/x
  3. Step 3: Cross multiply
    811.38x = 1,120.41 × 636.42
  4. Step 4: Simplify right side
    811.38x = 713,051.33
  5. Step 5: Solve for x
    x = 713,051.33/811.38
  6. Step 6: Final answer
    x = 878.81

Related Problems

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Half scale
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Double scale
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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.