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Finding the Fourth Proportional to 642.73, 964.10 and 155.78

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Solution

The fourth proportional to 642.73, 964.10 and 155.78 is: 233.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.73 : 964.10 = 155.78 : x
  2. Step 2: Convert to fraction form
    642.73/964.10 = 155.78/x
  3. Step 3: Cross multiply
    642.73x = 964.10 × 155.78
  4. Step 4: Simplify right side
    642.73x = 150,187.50
  5. Step 5: Solve for x
    x = 150,187.50/642.73
  6. Step 6: Final answer
    x = 233.67

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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 (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.