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Finding the Fourth Proportional to 643.96, 888.69 and 422.74

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Solution

The fourth proportional to 643.96, 888.69 and 422.74 is: 583.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.96 : 888.69 = 422.74 : x
  2. Step 2: Convert to fraction form
    643.96/888.69 = 422.74/x
  3. Step 3: Cross multiply
    643.96x = 888.69 × 422.74
  4. Step 4: Simplify right side
    643.96x = 375,684.81
  5. Step 5: Solve for x
    x = 375,684.81/643.96
  6. Step 6: Final answer
    x = 583.40

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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.