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Finding the Fourth Proportional to 641.72, 961.80 and 275.72

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Solution

The fourth proportional to 641.72, 961.80 and 275.72 is: 413.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.72 : 961.80 = 275.72 : x
  2. Step 2: Convert to fraction form
    641.72/961.80 = 275.72/x
  3. Step 3: Cross multiply
    641.72x = 961.80 × 275.72
  4. Step 4: Simplify right side
    641.72x = 265,187.50
  5. Step 5: Solve for x
    x = 265,187.50/641.72
  6. Step 6: Final answer
    x = 413.24

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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.