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Finding the Fourth Proportional to 640.97, 961.61 and 275.56

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Solution

The fourth proportional to 640.97, 961.61 and 275.56 is: 413.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.97 : 961.61 = 275.56 : x
  2. Step 2: Convert to fraction form
    640.97/961.61 = 275.56/x
  3. Step 3: Cross multiply
    640.97x = 961.61 × 275.56
  4. Step 4: Simplify right side
    640.97x = 264,975.07
  5. Step 5: Solve for x
    x = 264,975.07/640.97
  6. Step 6: Final answer
    x = 413.40

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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.