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Finding the Fourth Proportional to 687.20, 949.13 and 465.75

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Solution

The fourth proportional to 687.20, 949.13 and 465.75 is: 643.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.20 : 949.13 = 465.75 : x
  2. Step 2: Convert to fraction form
    687.20/949.13 = 465.75/x
  3. Step 3: Cross multiply
    687.20x = 949.13 × 465.75
  4. Step 4: Simplify right side
    687.20x = 442,054.97
  5. Step 5: Solve for x
    x = 442,054.97/687.20
  6. Step 6: Final answer
    x = 643.27

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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.