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Finding the Fourth Proportional to 691.38, 952.29 and 639.45

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Solution

The fourth proportional to 691.38, 952.29 and 639.45 is: 880.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.38 : 952.29 = 639.45 : x
  2. Step 2: Convert to fraction form
    691.38/952.29 = 639.45/x
  3. Step 3: Cross multiply
    691.38x = 952.29 × 639.45
  4. Step 4: Simplify right side
    691.38x = 608,941.84
  5. Step 5: Solve for x
    x = 608,941.84/691.38
  6. Step 6: Final answer
    x = 880.76

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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.