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Finding the Fourth Proportional to 717.39, 989.79 and 455.34

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Solution

The fourth proportional to 717.39, 989.79 and 455.34 is: 628.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    717.39 : 989.79 = 455.34 : x
  2. Step 2: Convert to fraction form
    717.39/989.79 = 455.34/x
  3. Step 3: Cross multiply
    717.39x = 989.79 × 455.34
  4. Step 4: Simplify right side
    717.39x = 450,690.98
  5. Step 5: Solve for x
    x = 450,690.98/717.39
  6. Step 6: Final answer
    x = 628.24

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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.