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Finding the Fourth Proportional to 491.30, 678.22 and 294.78

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Solution

The fourth proportional to 491.30, 678.22 and 294.78 is: 406.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.30 : 678.22 = 294.78 : x
  2. Step 2: Convert to fraction form
    491.30/678.22 = 294.78/x
  3. Step 3: Cross multiply
    491.30x = 678.22 × 294.78
  4. Step 4: Simplify right side
    491.30x = 199,925.69
  5. Step 5: Solve for x
    x = 199,925.69/491.30
  6. Step 6: Final answer
    x = 406.93

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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.