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Finding the Fourth Proportional to 643.83, 888.51 and 378.45

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Solution

The fourth proportional to 643.83, 888.51 and 378.45 is: 522.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.83 : 888.51 = 378.45 : x
  2. Step 2: Convert to fraction form
    643.83/888.51 = 378.45/x
  3. Step 3: Cross multiply
    643.83x = 888.51 × 378.45
  4. Step 4: Simplify right side
    643.83x = 336,258.03
  5. Step 5: Solve for x
    x = 336,258.03/643.83
  6. Step 6: Final answer
    x = 522.28

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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.