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Finding the Fourth Proportional to 730.71, 1,008.36 and 420.21

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Solution

The fourth proportional to 730.71, 1,008.36 and 420.21 is: 579.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    730.71 : 1,008.36 = 420.21 : x
  2. Step 2: Convert to fraction form
    730.71/1,008.36 = 420.21/x
  3. Step 3: Cross multiply
    730.71x = 1,008.36 × 420.21
  4. Step 4: Simplify right side
    730.71x = 423,722.96
  5. Step 5: Solve for x
    x = 423,722.96/730.71
  6. Step 6: Final answer
    x = 579.88

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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.