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Finding the Fourth Proportional to 980.20, 1,470.55 and 286.88

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Solution

The fourth proportional to 980.20, 1,470.55 and 286.88 is: 430.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    980.20 : 1,470.55 = 286.88 : x
  2. Step 2: Convert to fraction form
    980.20/1,470.55 = 286.88/x
  3. Step 3: Cross multiply
    980.20x = 1,470.55 × 286.88
  4. Step 4: Simplify right side
    980.20x = 421,871.38
  5. Step 5: Solve for x
    x = 421,871.38/980.20
  6. Step 6: Final answer
    x = 430.39

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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.