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Finding the Fourth Proportional to 643.06, 887.86 and 422.39

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Solution

The fourth proportional to 643.06, 887.86 and 422.39 is: 583.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.06 : 887.86 = 422.39 : x
  2. Step 2: Convert to fraction form
    643.06/887.86 = 422.39/x
  3. Step 3: Cross multiply
    643.06x = 887.86 × 422.39
  4. Step 4: Simplify right side
    643.06x = 375,017.69
  5. Step 5: Solve for x
    x = 375,017.69/643.06
  6. Step 6: Final answer
    x = 583.18

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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.