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Finding the Fourth Proportional to 688.28, 950.80 and 491.44

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Solution

The fourth proportional to 688.28, 950.80 and 491.44 is: 678.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.28 : 950.80 = 491.44 : x
  2. Step 2: Convert to fraction form
    688.28/950.80 = 491.44/x
  3. Step 3: Cross multiply
    688.28x = 950.80 × 491.44
  4. Step 4: Simplify right side
    688.28x = 467,261.15
  5. Step 5: Solve for x
    x = 467,261.15/688.28
  6. Step 6: Final answer
    x = 678.88

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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.