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Finding the Fourth Proportional to 860, 1,289.76 and 282.80

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Solution

The fourth proportional to 860, 1,289.76 and 282.80 is: 424.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    860 : 1,289.76 = 282.80 : x
  2. Step 2: Convert to fraction form
    860/1,289.76 = 282.80/x
  3. Step 3: Cross multiply
    860x = 1,289.76 × 282.80
  4. Step 4: Simplify right side
    860x = 364,744.13
  5. Step 5: Solve for x
    x = 364,744.13/860
  6. Step 6: Final answer
    x = 424.12

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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.