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Finding the Fourth Proportional to 643.74, 888.38 and 378.19

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Solution

The fourth proportional to 643.74, 888.38 and 378.19 is: 521.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.74 : 888.38 = 378.19 : x
  2. Step 2: Convert to fraction form
    643.74/888.38 = 378.19/x
  3. Step 3: Cross multiply
    643.74x = 888.38 × 378.19
  4. Step 4: Simplify right side
    643.74x = 335,976.43
  5. Step 5: Solve for x
    x = 335,976.43/643.74
  6. Step 6: Final answer
    x = 521.91

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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.