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Finding the Fourth Proportional to 651.79, 978 and 286.89

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Solution

The fourth proportional to 651.79, 978 and 286.89 is: 430.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.79 : 978 = 286.89 : x
  2. Step 2: Convert to fraction form
    651.79/978 = 286.89/x
  3. Step 3: Cross multiply
    651.79x = 978 × 286.89
  4. Step 4: Simplify right side
    651.79x = 280,578.42
  5. Step 5: Solve for x
    x = 280,578.42/651.79
  6. Step 6: Final answer
    x = 430.47

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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.