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Finding the Fourth Proportional to 643.12, 887.70 and 622.60

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Solution

The fourth proportional to 643.12, 887.70 and 622.60 is: 859.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.12 : 887.70 = 622.60 : x
  2. Step 2: Convert to fraction form
    643.12/887.70 = 622.60/x
  3. Step 3: Cross multiply
    643.12x = 887.70 × 622.60
  4. Step 4: Simplify right side
    643.12x = 552,682.02
  5. Step 5: Solve for x
    x = 552,682.02/643.12
  6. Step 6: Final answer
    x = 859.38

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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.