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Finding the Fourth Proportional to 630.80, 881.20 and 630.80

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Solution

The fourth proportional to 630.80, 881.20 and 630.80 is: 881.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.80 : 881.20 = 630.80 : x
  2. Step 2: Convert to fraction form
    630.80/881.20 = 630.80/x
  3. Step 3: Cross multiply
    630.80x = 881.20 × 630.80
  4. Step 4: Simplify right side
    630.80x = 555,860.96
  5. Step 5: Solve for x
    x = 555,860.96/630.80
  6. Step 6: Final answer
    x = 881.20

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Half scale
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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.