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Finding the Fourth Proportional to 617.64, 853.43 and 485.20

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Solution

The fourth proportional to 617.64, 853.43 and 485.20 is: 670.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    617.64 : 853.43 = 485.20 : x
  2. Step 2: Convert to fraction form
    617.64/853.43 = 485.20/x
  3. Step 3: Cross multiply
    617.64x = 853.43 × 485.20
  4. Step 4: Simplify right side
    617.64x = 414,084.24
  5. Step 5: Solve for x
    x = 414,084.24/617.64
  6. Step 6: Final answer
    x = 670.43

Related Problems

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Double scale
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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.