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Finding the Fourth Proportional to 643.37, 887.18 and 477.90

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Solution

The fourth proportional to 643.37, 887.18 and 477.90 is: 659.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.37 : 887.18 = 477.90 : x
  2. Step 2: Convert to fraction form
    643.37/887.18 = 477.90/x
  3. Step 3: Cross multiply
    643.37x = 887.18 × 477.90
  4. Step 4: Simplify right side
    643.37x = 423,980.93
  5. Step 5: Solve for x
    x = 423,980.93/643.37
  6. Step 6: Final answer
    x = 659.01

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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.