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Finding the Fourth Proportional to 687.11, 948.18 and 422

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Solution

The fourth proportional to 687.11, 948.18 and 422 is: 582.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.11 : 948.18 = 422 : x
  2. Step 2: Convert to fraction form
    687.11/948.18 = 422/x
  3. Step 3: Cross multiply
    687.11x = 948.18 × 422
  4. Step 4: Simplify right side
    687.11x = 400,131.96
  5. Step 5: Solve for x
    x = 400,131.96/687.11
  6. Step 6: Final answer
    x = 582.34

Related Problems

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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.