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Finding the Fourth Proportional to 738.39, 1,018.40 and 688.71

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Solution

The fourth proportional to 738.39, 1,018.40 and 688.71 is: 949.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    738.39 : 1,018.40 = 688.71 : x
  2. Step 2: Convert to fraction form
    738.39/1,018.40 = 688.71/x
  3. Step 3: Cross multiply
    738.39x = 1,018.40 × 688.71
  4. Step 4: Simplify right side
    738.39x = 701,378.82
  5. Step 5: Solve for x
    x = 701,378.82/738.39
  6. Step 6: Final answer
    x = 949.88

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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.