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Finding the Fourth Proportional to 684.40, 944.43 and 389.71

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Solution

The fourth proportional to 684.40, 944.43 and 389.71 is: 537.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.40 : 944.43 = 389.71 : x
  2. Step 2: Convert to fraction form
    684.40/944.43 = 389.71/x
  3. Step 3: Cross multiply
    684.40x = 944.43 × 389.71
  4. Step 4: Simplify right side
    684.40x = 368,053.82
  5. Step 5: Solve for x
    x = 368,053.82/684.40
  6. Step 6: Final answer
    x = 537.78

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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.