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Finding the Fourth Proportional to 643.51, 888.06 and 381.38

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Solution

The fourth proportional to 643.51, 888.06 and 381.38 is: 526.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.51 : 888.06 = 381.38 : x
  2. Step 2: Convert to fraction form
    643.51/888.06 = 381.38/x
  3. Step 3: Cross multiply
    643.51x = 888.06 × 381.38
  4. Step 4: Simplify right side
    643.51x = 338,685.31
  5. Step 5: Solve for x
    x = 338,685.31/643.51
  6. Step 6: Final answer
    x = 526.31

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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.