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Finding the Fourth Proportional to 491.50, 678.20 and 314.62

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Solution

The fourth proportional to 491.50, 678.20 and 314.62 is: 434.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.50 : 678.20 = 314.62 : x
  2. Step 2: Convert to fraction form
    491.50/678.20 = 314.62/x
  3. Step 3: Cross multiply
    491.50x = 678.20 × 314.62
  4. Step 4: Simplify right side
    491.50x = 213,373.71
  5. Step 5: Solve for x
    x = 213,373.71/491.50
  6. Step 6: Final answer
    x = 434.13

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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.