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Finding the Fourth Proportional to 456.80, 681.24 and 388.76

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Solution

The fourth proportional to 456.80, 681.24 and 388.76 is: 579.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    456.80 : 681.24 = 388.76 : x
  2. Step 2: Convert to fraction form
    456.80/681.24 = 388.76/x
  3. Step 3: Cross multiply
    456.80x = 681.24 × 388.76
  4. Step 4: Simplify right side
    456.80x = 264,838.86
  5. Step 5: Solve for x
    x = 264,838.86/456.80
  6. Step 6: Final answer
    x = 579.77

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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.