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Finding the Fourth Proportional to 486.80, 730.20 and 478.70

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Solution

The fourth proportional to 486.80, 730.20 and 478.70 is: 718.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.80 : 730.20 = 478.70 : x
  2. Step 2: Convert to fraction form
    486.80/730.20 = 478.70/x
  3. Step 3: Cross multiply
    486.80x = 730.20 × 478.70
  4. Step 4: Simplify right side
    486.80x = 349,546.74
  5. Step 5: Solve for x
    x = 349,546.74/486.80
  6. Step 6: Final answer
    x = 718.05

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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.