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Finding the Fourth Proportional to 639.78, 957.60 and 523.23

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Solution

The fourth proportional to 639.78, 957.60 and 523.23 is: 783.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.78 : 957.60 = 523.23 : x
  2. Step 2: Convert to fraction form
    639.78/957.60 = 523.23/x
  3. Step 3: Cross multiply
    639.78x = 957.60 × 523.23
  4. Step 4: Simplify right side
    639.78x = 501,045.05
  5. Step 5: Solve for x
    x = 501,045.05/639.78
  6. Step 6: Final answer
    x = 783.15

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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.