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Finding the Fourth Proportional to 643.56, 887.72 and 475.34

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Solution

The fourth proportional to 643.56, 887.72 and 475.34 is: 655.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.56 : 887.72 = 475.34 : x
  2. Step 2: Convert to fraction form
    643.56/887.72 = 475.34/x
  3. Step 3: Cross multiply
    643.56x = 887.72 × 475.34
  4. Step 4: Simplify right side
    643.56x = 421,968.82
  5. Step 5: Solve for x
    x = 421,968.82/643.56
  6. Step 6: Final answer
    x = 655.68

Related Problems

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Double scale
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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.