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Finding the Fourth Proportional to 860.03, 1,289.38 and 427.49

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Solution

The fourth proportional to 860.03, 1,289.38 and 427.49 is: 640.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.03 : 1,289.38 = 427.49 : x
  2. Step 2: Convert to fraction form
    860.03/1,289.38 = 427.49/x
  3. Step 3: Cross multiply
    860.03x = 1,289.38 × 427.49
  4. Step 4: Simplify right side
    860.03x = 551,197.06
  5. Step 5: Solve for x
    x = 551,197.06/860.03
  6. Step 6: Final answer
    x = 640.90

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1.5x scale

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.