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Finding the Fourth Proportional to 643.50, 887.94 and 422.51

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Solution

The fourth proportional to 643.50, 887.94 and 422.51 is: 583.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.50 : 887.94 = 422.51 : x
  2. Step 2: Convert to fraction form
    643.50/887.94 = 422.51/x
  3. Step 3: Cross multiply
    643.50x = 887.94 × 422.51
  4. Step 4: Simplify right side
    643.50x = 375,159.09
  5. Step 5: Solve for x
    x = 375,159.09/643.50
  6. Step 6: Final answer
    x = 583.00

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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.