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Finding the Fourth Proportional to 626.80, 939.76 and 318.28

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Solution

The fourth proportional to 626.80, 939.76 and 318.28 is: 477.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    626.80 : 939.76 = 318.28 : x
  2. Step 2: Convert to fraction form
    626.80/939.76 = 318.28/x
  3. Step 3: Cross multiply
    626.80x = 939.76 × 318.28
  4. Step 4: Simplify right side
    626.80x = 299,106.81
  5. Step 5: Solve for x
    x = 299,106.81/626.80
  6. Step 6: Final answer
    x = 477.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.