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Finding the Fourth Proportional to 418.80, 623.86 and 411.90

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Solution

The fourth proportional to 418.80, 623.86 and 411.90 is: 613.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.80 : 623.86 = 411.90 : x
  2. Step 2: Convert to fraction form
    418.80/623.86 = 411.90/x
  3. Step 3: Cross multiply
    418.80x = 623.86 × 411.90
  4. Step 4: Simplify right side
    418.80x = 256,967.93
  5. Step 5: Solve for x
    x = 256,967.93/418.80
  6. Step 6: Final answer
    x = 613.58

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.