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Finding the Fourth Proportional to 643.19, 886.76 and 422.06

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Solution

The fourth proportional to 643.19, 886.76 and 422.06 is: 581.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.19 : 886.76 = 422.06 : x
  2. Step 2: Convert to fraction form
    643.19/886.76 = 422.06/x
  3. Step 3: Cross multiply
    643.19x = 886.76 × 422.06
  4. Step 4: Simplify right side
    643.19x = 374,259.38
  5. Step 5: Solve for x
    x = 374,259.38/643.19
  6. Step 6: Final answer
    x = 581.88

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Similar ratio
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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.