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Finding the Fourth Proportional to 491.16, 678.13 and 378.92

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Solution

The fourth proportional to 491.16, 678.13 and 378.92 is: 523.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.16 : 678.13 = 378.92 : x
  2. Step 2: Convert to fraction form
    491.16/678.13 = 378.92/x
  3. Step 3: Cross multiply
    491.16x = 678.13 × 378.92
  4. Step 4: Simplify right side
    491.16x = 256,957.77
  5. Step 5: Solve for x
    x = 256,957.77/491.16
  6. Step 6: Final answer
    x = 523.17

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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.