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Finding the Fourth Proportional to 909.20, 1,255.28 and 630.28

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Solution

The fourth proportional to 909.20, 1,255.28 and 630.28 is: 870.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    909.20 : 1,255.28 = 630.28 : x
  2. Step 2: Convert to fraction form
    909.20/1,255.28 = 630.28/x
  3. Step 3: Cross multiply
    909.20x = 1,255.28 × 630.28
  4. Step 4: Simplify right side
    909.20x = 791,177.88
  5. Step 5: Solve for x
    x = 791,177.88/909.20
  6. Step 6: Final answer
    x = 870.19

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.