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Finding the Fourth Proportional to 811.86, 1,120.38 and 457.79

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Solution

The fourth proportional to 811.86, 1,120.38 and 457.79 is: 631.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.86 : 1,120.38 = 457.79 : x
  2. Step 2: Convert to fraction form
    811.86/1,120.38 = 457.79/x
  3. Step 3: Cross multiply
    811.86x = 1,120.38 × 457.79
  4. Step 4: Simplify right side
    811.86x = 512,898.76
  5. Step 5: Solve for x
    x = 512,898.76/811.86
  6. Step 6: Final answer
    x = 631.76

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Double scale
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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.