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Finding the Fourth Proportional to 679.28, 1,018.10 and 486.50

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Solution

The fourth proportional to 679.28, 1,018.10 and 486.50 is: 729.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.28 : 1,018.10 = 486.50 : x
  2. Step 2: Convert to fraction form
    679.28/1,018.10 = 486.50/x
  3. Step 3: Cross multiply
    679.28x = 1,018.10 × 486.50
  4. Step 4: Simplify right side
    679.28x = 495,305.65
  5. Step 5: Solve for x
    x = 495,305.65/679.28
  6. Step 6: Final answer
    x = 729.16

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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.