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Finding the Fourth Proportional to 642.75, 887.12 and 377.20

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Solution

The fourth proportional to 642.75, 887.12 and 377.20 is: 520.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.75 : 887.12 = 377.20 : x
  2. Step 2: Convert to fraction form
    642.75/887.12 = 377.20/x
  3. Step 3: Cross multiply
    642.75x = 887.12 × 377.20
  4. Step 4: Simplify right side
    642.75x = 334,621.66
  5. Step 5: Solve for x
    x = 334,621.66/642.75
  6. Step 6: Final answer
    x = 520.61

Related Problems

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Double scale
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Similar ratio
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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.