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Finding the Fourth Proportional to 643.74, 888.37 and 378.13

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Solution

The fourth proportional to 643.74, 888.37 and 378.13 is: 521.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.74 : 888.37 = 378.13 : x
  2. Step 2: Convert to fraction form
    643.74/888.37 = 378.13/x
  3. Step 3: Cross multiply
    643.74x = 888.37 × 378.13
  4. Step 4: Simplify right side
    643.74x = 335,916.18
  5. Step 5: Solve for x
    x = 335,916.18/643.74
  6. Step 6: Final answer
    x = 521.82

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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.