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Finding the Fourth Proportional to 721.38, 995.55 and 406.65

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Solution

The fourth proportional to 721.38, 995.55 and 406.65 is: 561.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.38 : 995.55 = 406.65 : x
  2. Step 2: Convert to fraction form
    721.38/995.55 = 406.65/x
  3. Step 3: Cross multiply
    721.38x = 995.55 × 406.65
  4. Step 4: Simplify right side
    721.38x = 404,840.41
  5. Step 5: Solve for x
    x = 404,840.41/721.38
  6. Step 6: Final answer
    x = 561.20

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1.5x scale

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.