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Finding the Fourth Proportional to 686.85, 948.15 and 438.49

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Solution

The fourth proportional to 686.85, 948.15 and 438.49 is: 605.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.85 : 948.15 = 438.49 : x
  2. Step 2: Convert to fraction form
    686.85/948.15 = 438.49/x
  3. Step 3: Cross multiply
    686.85x = 948.15 × 438.49
  4. Step 4: Simplify right side
    686.85x = 415,754.29
  5. Step 5: Solve for x
    x = 415,754.29/686.85
  6. Step 6: Final answer
    x = 605.31

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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.