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Finding the Fourth Proportional to 821.64, 1,134.15 and 490.17

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Solution

The fourth proportional to 821.64, 1,134.15 and 490.17 is: 676.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    821.64 : 1,134.15 = 490.17 : x
  2. Step 2: Convert to fraction form
    821.64/1,134.15 = 490.17/x
  3. Step 3: Cross multiply
    821.64x = 1,134.15 × 490.17
  4. Step 4: Simplify right side
    821.64x = 555,926.31
  5. Step 5: Solve for x
    x = 555,926.31/821.64
  6. Step 6: Final answer
    x = 676.61

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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.