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Finding the Fourth Proportional to 491.48, 678.23 and 281.66

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Solution

The fourth proportional to 491.48, 678.23 and 281.66 is: 388.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.48 : 678.23 = 281.66 : x
  2. Step 2: Convert to fraction form
    491.48/678.23 = 281.66/x
  3. Step 3: Cross multiply
    491.48x = 678.23 × 281.66
  4. Step 4: Simplify right side
    491.48x = 191,025.46
  5. Step 5: Solve for x
    x = 191,025.46/491.48
  6. Step 6: Final answer
    x = 388.68

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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.